ICG SERVICES, INC.,
                                        as Issuer


                                         and


                     NORWEST BANK COLORADO, NATIONAL ASSOCIATION,
                                        as Trustee



                                 -------------------

                                      Indenture

                            Dated as of February 12, 1998

                                 -------------------


                          10% Senior Discount Notes due 2008


          =================================================================


          


                                CROSS-REFERENCE TABLE
                                ---------------------



          TIA Sections                             Indenture Sections
          ------------                             ------------------

          S.310(a)(1) . . . . . . . . . . . . . .         7.10
               (a)(2) . . . . . . . . . . . . . .         7.10
               (b)  . . . . . . . . . . . . . . .         7.08
          S.313(c)  . . . . . . . . . . . . . . .         7.06; 10.02
          S.314(a)  . . . . . . . . . . . . . . .         4.18; 10.02
               (a)(4) . . . . . . . . . . . . . .         4.17; 10.02
               (c)(1) . . . . . . . . . . . . . .         10.03
               (c)(2) . . . . . . . . . . . . . .         10.03
               (e)  . . . . . . . . . . . . . . .         10.04
          S.315(b)  . . . . . . . . . . . . . . .         7.05; 10.02
          S.316(a)(1)(A)  . . . . . . . . . . . .         6.05
               (a)(1)(B)  . . . . . . . . . . . .         6.04
               (b)  . . . . . . . . . . . . . . .         6.07
          S.317(a)(1) . . . . . . . . . . . . . .         6.08
               (a)(2) . . . . . . . . . . . . . .         6.09
          S.318(a)  . . . . . . . . . . . . . . .         10.01
               (c)  . . . . . . . . . . . . . . .         10.01



          Note:   The Cross-Reference Table shall not for any purpose be
                  deemed to be a part of the Indenture.


          


                                  TABLE OF CONTENTS
                                                                       Page

          RECITALS OF THE COMPANY . . . . . . . . . . . . . . . . . . .   1

                                     ARTICLE ONE
                      DEFINITIONS AND INCORPORATION BY REFERENCE

          SECTION 1.01.  Definitions  . . . . . . . . . . . . . . . . .   1
          SECTION 1.02.  Incorporation by Reference of
                            Trust Indenture Act   . . . . . . . . . . .  25
          SECTION 1.03.  Rules of Construction  . . . . . . . . . . . .  25

                                     ARTICLE TWO
                                      THE NOTES

          SECTION 2.01.  Form and Dating  . . . . . . . . . . . . . . .  26
          SECTION 2.02.  Restrictive Legends  . . . . . . . . . . . . .  27
          SECTION 2.03.  Execution, Authentication and Denominations  .  29
          SECTION 2.04.  Registrar and Paying Agent . . . . . . . . . .  30
          SECTION 2.05.  Paying Agent to Hold Money in Trust  . . . . .  31
          SECTION 2.06.  Transfer and Exchange  . . . . . . . . . . . .  31
          SECTION 2.07.  Book-Entry Provisions for Global Notes . . . .  32
          SECTION 2.08.  Special Transfer Provisions  . . . . . . . . .  34
          SECTION 2.09.  Replacement Notes  . . . . . . . . . . . . . .  37
          SECTION 2.10.  Outstanding Notes  . . . . . . . . . . . . . .  38
          SECTION 2.11.  Temporary Notes  . . . . . . . . . . . . . . .  38
          SECTION 2.12.  Cancellation . . . . . . . . . . . . . . . . .  39
          SECTION 2.13.  CUSIP Numbers  . . . . . . . . . . . . . . . .  39
          SECTION 2.14.  Defaulted Interest . . . . . . . . . . . . . .  39
          SECTION 2.15.  Issuance of Additional Notes . . . . . . . . .  39

                                    ARTICLE THREE
                                      REDEMPTION

          SECTION 3.01.  Right of Redemption  . . . . . . . . . . . . .  40
          SECTION 3.02.  Notices to Trustee . . . . . . . . . . . . . .  40
          SECTION 3.03.  Selection of Notes to Be Redeemed  . . . . . .  40
          SECTION 3.04.  Notice of Redemption . . . . . . . . . . . . .  41
          SECTION 3.05.  Effect of Notice of Redemption . . . . . . . .  42
          SECTION 3.06.  Deposit of Redemption Price  . . . . . . . . .  42
          SECTION 3.07.  Payment of Notes Called for Redemption . . . .  42
          SECTION 3.08.  Notes Redeemed in Part . . . . . . . . . . . .  43

          --------------------
          Note: The Table of Contents shall not for any purposes be deemed
                to be a part of the Indenture.

          

                                     ARTICLE FOUR
                                      COVENANTS

          SECTION 4.01.  Payment of Notes . . . . . . . . . . . . . . .  43
          SECTION 4.02.  Maintenance of Office or Agency  . . . . . . .  43
          SECTION 4.03.  Limitation on Indebtedness . . . . . . . . . .  44
          SECTION 4.04.  Limitation on Restricted Payments  . . . . . .  47
          SECTION 4.05.  Limitation on Dividend and Other
                            Payment Restrictions Affecting
                            Restricted Subsidiaries   . . . . . . . . .  50
          SECTION 4.06.  Limitation on the Issuance and Sale of
                            Capital Stock of Restricted Subsidiaries  .  52
          SECTION 4.07.  Limitation on Issuances of Guarantees by
                            Restricted Subsidiaries   . . . . . . . . .  52
          SECTION 4.08.  Limitation on Transactions with Shareholders
                            and Affiliates  . . . . . . . . . . . . . .  53
          SECTION 4.09.  Limitation on Liens  . . . . . . . . . . . . .  54
          SECTION 4.10.  Limitation on Sale-Leaseback Transactions  . .  54
          SECTION 4.11.  Limitation on Asset Sales  . . . . . . . . . .  55
          SECTION 4.12.  Repurchase of Notes upon a Change of Control .  57
          SECTION 4.13.  Existence  . . . . . . . . . . . . . . . . . .  57
          SECTION 4.14.  Payment of Taxes and Other Claims  . . . . . .  57
          SECTION 4.15.  Maintenance of Properties and Insurance  . . .  57
          SECTION 4.16.  Notice of Defaults . . . . . . . . . . . . . .  58
          SECTION 4.17.  Compliance Certificates  . . . . . . . . . . .  58
          SECTION 4.18.  Commission Reports and Reports to Holders  . .  59
          SECTION 4.19.  Waiver of Stay, Extension or Usury Laws  . . .  59

                                     ARTICLE FIVE
                                SUCCESSOR CORPORATION

          SECTION 5.01.  When Company May Merge, Etc. . . . . . . . . .  60
          SECTION 5.02.  Successor Substituted  . . . . . . . . . . . .  61

                                     ARTICLE SIX
                                 DEFAULT AND REMEDIES

          SECTION 6.01.  Events of Default  . . . . . . . . . . . . . .  61
          SECTION 6.02.  Acceleration . . . . . . . . . . . . . . . . .  62
          SECTION 6.03.  Other Remedies . . . . . . . . . . . . . . . .  63
          SECTION 6.04.  Waiver of Past Defaults  . . . . . . . . . . .  64
          SECTION 6.05.  Control by Majority  . . . . . . . . . . . . .  64
          SECTION 6.06.  Limitation on Suits  . . . . . . . . . . . . .  64
          SECTION 6.07.  Rights of Holders to Receive Payment . . . . .  65
          SECTION 6.08.  Collection Suit by Trustee . . . . . . . . . .  65
          SECTION 6.09.  Trustee May File Proofs of Claim . . . . . . .  65
          SECTION 6.10.  Priorities . . . . . . . . . . . . . . . . . .  66
          SECTION 6.11.  Undertaking for Costs  . . . . . . . . . . . .  66
          SECTION 6.12.  Restoration of Rights and Remedies . . . . . .  66
          SECTION 6.13.  Rights and Remedies Cumulative . . . . . . . .  67
          SECTION 6.14.  Delay or Omission Not Waiver . . . . . . . . .  67


          

                                    ARTICLE SEVEN
                                       TRUSTEE

          SECTION 7.01.  General  . . . . . . . . . . . . . . . . . . .  67
          SECTION 7.02.  Certain Rights of Trustee  . . . . . . . . . .  67
          SECTION 7.03.  Individual Rights of Trustee . . . . . . . . .  68
          SECTION 7.04.  Trustee's Disclaimer . . . . . . . . . . . . .  69
          SECTION 7.05.  Notice of Default  . . . . . . . . . . . . . .  69
          SECTION 7.06.  Reports by Trustee to Holders  . . . . . . . .  69
          SECTION 7.07.  Compensation and Indemnity . . . . . . . . . .  69
          SECTION 7.08.  Replacement of Trustee . . . . . . . . . . . .  70
          SECTION 7.09.  Successor Trustee by Merger, Etc.  . . . . . .  71
          SECTION 7.10.  Eligibility  . . . . . . . . . . . . . . . . .  71
          SECTION 7.11.  Money Held in Trust  . . . . . . . . . . . . .  71
          SECTION 7.12.  Withholding Taxes  . . . . . . . . . . . . . .  71

                                    ARTICLE EIGHT
                                DISCHARGE OF INDENTURE

          SECTION 8.01. Termination of the Company's Obligations  . . .  72
          SECTION 8.02.  Defeasance and Discharge of Indenture  . . . .  73
          SECTION 8.03.  Defeasance of Certain Obligations  . . . . . .  74
          SECTION 8.04.  Application of Trust Money . . . . . . . . . .  75
          SECTION 8.05.  Repayment to Company . . . . . . . . . . . . .  75
          SECTION 8.06.  Reinstatement  . . . . . . . . . . . . . . . .  76
          SECTION 8.07.  Defeasance and Certain Other
                            Events of Default   . . . . . . . . . . . .  76

                                     ARTICLE NINE
                         AMENDMENTS, SUPPLEMENTS AND WAIVERS

          SECTION 9.01.  Without Consent of Holders . . . . . . . . . .  76
          SECTION 9.02.  With Consent of Holders  . . . . . . . . . . .  77
          SECTION 9.03.  Revocation and Effect of Consent . . . . . . .  78
          SECTION 9.04.  Notation on or Exchange of Notes . . . . . . .  78
          SECTION 9.05.  Trustee to Sign Amendments, Etc. . . . . . . .  79
          SECTION 9.06.  Conformity with Trust Indenture Act  . . . . .  79



          

                                     ARTICLE TEN
                                    MISCELLANEOUS

          SECTION 10.01.  Trust Indenture Act of 1939 . . . . . . . . .  79
          SECTION 10.02.  Notices . . . . . . . . . . . . . . . . . . .  79
          SECTION 10.03.  Certificate and Opinion As to
                            Conditions Precedent  . . . . . . . . . . .  80
          SECTION 10.04.  Statements Required in Certificate
                            or Opinion  . . . . . . . . . . . . . . . .  81
          SECTION 10.05.  Rules by Trustee, Paying Agent 
                            or Registrar  . . . . . . . . . . . . . . .  81
          SECTION 10.06.  Payment Date Other Than a Business Day  . . .  81
          SECTION 10.07.  Governing Law; Submission to Jurisdiction . .  81
          SECTION 10.08.  No Adverse Interpretation of
                            Other Agreements  . . . . . . . . . . . . .  81
          SECTION 10.09.  No Recourse Against Others  . . . . . . . . .  82
          SECTION 10.10.  Successors  . . . . . . . . . . . . . . . . .  82
          SECTION 10.11.  Duplicate Originals . . . . . . . . . . . . .  82
          SECTION 10.12.  Separability  . . . . . . . . . . . . . . . .  82
          SECTION 10.13.  Table of Contents, Headings, Etc. . . . . . .  82


            EXHIBIT A     Form of Note  . . . . . . . . . . . . . . . . A-1
            EXHIBIT B     Form of Certificate   . . . . . . . . . . . . B-1
            EXHIBIT C     Form of Certificate to Be Delivered
                            in Connection with Transfers Pursuant
                            to Regulation S   . . . . . . . . . . . . . C-1
            EXHIBIT D     Form of Certificate to Be Delivered
                            in Connection with Transfers to
                            Non-QIB Accredited Investors  . . . . . . . D-1


          


          

          
                    INDENTURE, dated as of February 12, 1998, between ICG
          SERVICES INC., a Delaware corporation (the "Company"), and 
                                                      -------
          NORWEST BANK COLORADO, NATIONAL ASSOCIATION (the "Trustee").
                                                            -------


                               RECITALS OF THE COMPANY

                    The Company has duly authorized the execution and
          delivery of this Indenture to provide for the issuance from time
          to time of 10% Senior Discount Notes due 2008 (the "Notes") 
                                                              -----
          issuable as provided in this Indenture.  Pursuant to the terms of
          a Placement Agreement dated February 9, 1998 (the "Placement 
                                                             ---------
          Agreement") among the Company, NETCOM On-Line Communication 
          ---------
          Services, Inc. and Morgan Stanley & Co. Incorporated, the Company
          has agreed to issue and sell $490,000,000 aggregate principal
          amount at maturity of the Notes.  All things necessary to make
          this Indenture a valid agreement of the Company, in accordance
          with its terms, have been done, and the Company has done all
          things necessary to make the Notes, when executed by the Company
          and authenticated and delivered by the Trustee hereunder and duly
          issued by the Company, the valid obligations of the Company as
          hereinafter provided.

                    This Indenture is subject to, and shall be governed by,
          the provisions of the Trust Indenture Act of 1939, as amended,
          that are required to be a part of and to govern indentures
          qualified under the Trust Indenture Act of 1939, as amended.

                    For and in consideration of the premises and the
          purchase of the Notes by the Holders thereof, it is mutually
          covenanted and agreed, for the equal and proportionate benefit of
          all Holders, as follows.


                                     ARTICLE ONE
                      DEFINITIONS AND INCORPORATION BY REFERENCE

                    SECTION 1.01.  Definitions.
                                   -----------

               "Accreted Value" means, for any Specified Date, the amount
          calculated pursuant to (i), (ii), (iii) or (iv) for each $1,000
          principal amount at maturity of Notes:

                    (i)    if the Specified Date occurs on one of the
               following dates (each a "Semi-Annual Accrual Date"), the 
                                        ------------------------
               Accreted Value will equal the amount set forth below for
               such Semi-Annual Accrual Date:

                               SEMI-ANNUAL        ACCRETED
                              ACCRUAL DATE         VALUE
                              ------------          ----

                            August 15, 1998        $ 644.60
                            February 15, 1999      $ 676.83
                            August 15, 1999        $ 710.68
                            February 15, 2000      $ 746.21
                            August 15, 2000        $ 783.52
                            February 15, 2001      $ 822.70
                            August 15, 2001        $ 863.83
                            February 15, 2002      $ 907.02
                            August 15, 2002        $ 952.38
                            February 15, 2003    $ 1,000.00

                    (ii)   if the Specified Date occurs before the first
               Semi-Annual Accrual Date, the Accreted Value will equal the
               sum of (a) the original issue price and (b) an amount equal
               to the product of (1) the Accreted Value for the first Semi-
               Annual Accrual Date less the original issue price multiplied
                                                                 ----------
               by (2) a fraction, the numerator of which is the number of
               days from the issue date of the Notes to the Specified Date,
               using a 360-day year of twelve 30-day months, and the
               denominator of which is the number of days from the Closing
               Date to the first Semi-Annual Accrual Date, using a 360-day
               year of twelve 30-day months;

                    (iii)  if the Specified Date occurs between two Semi-
               Annual Accrual Dates, the Accreted Value will equal the sum
               of (a) the Accreted Value for the Semi-Annual Accrual Date
               immediately preceding such Specified Date and (b) an amount
               equal to the product of (1) the Accreted Value for the
               immediately following Semi-Annual Accrual Date less the
               Accreted Value for the immediately preceding Semi-Annual
               Accrual Date multiplied by (2) a fraction, the numerator of
               which is the number of days from the immediately preceding
               Semi-Annual Accrual Date to the Specified Date, using a 360-
               day year of twelve 30-day months, and the denominator of
               which is 180; or

                    (iv)   if the Specified Date occurs after the last
               Semi-Annual Accrual Date, the Accreted Value will equal
               $1,000.

               "Acquired Indebtedness" means Indebtedness of a Person
          existing at the time such Person becomes a Restricted Subsidiary
          or assumed in connection with an Asset Acquisition by a
          Restricted Subsidiary and not Incurred in connection with, or in
          anticipation of, such Person becoming a Restricted Subsidiary or
          such Asset Acquisition.

               "Adjusted Consolidated Net Income" means, for any period,
          the aggregate net income (or loss) of the Company and its
          Restricted Subsidiaries for such period determined in conformity
          with GAAP; provided that the following items shall be excluded in
                     --------
          computing Adjusted Consolidated Net Income (without duplication): 
          (i) the net income (or loss) of any Person that is not a
          Restricted Subsidiary (or is an Unrestricted Subsidiary), except
          to the extent of the amount of dividends or other distributions
          actually paid to the Company or any of its Restricted
          Subsidiaries by such Person or an Unrestricted Subsidiary during
          such period; (ii) solely for the purposes of calculating the
          amount of Restricted Payments that may be made pursuant to clause
          (C) of the first paragraph of Section 4.04 hereof (and in such
          case, except to the extent includable pursuant to clause (i)
          above), the net income (or loss) of any Person accrued prior to
          the date it becomes a Restricted Subsidiary or is merged into or
          consolidated with the Company or any of its Restricted
          Subsidiaries or all or substantially all of the property and
          assets of such Person are acquired by the Company or any of its
          Restricted Subsidiaries; (iii) the net income of any Restricted
          Subsidiary to the extent that the declaration or payment of
          dividends or similar distributions by such Restricted Subsidiary
          of such net income is not at the time permitted by the operation
          of the terms of its charter or any agreement, instrument,
          judgment, decree, order, statute, rule or governmental regulation
          applicable to such Restricted Subsidiary (except to the extent
          such restriction has been legally waived); (iv) any gains or
          losses (on an after-tax basis) attributable to Asset Sales or the
          termination of discontinued operations; (v) except for purposes
          of calculating the amount of Restricted Payments that may be made
          pursuant to clause (C) of the first paragraph of Section 4.04,
          any amount paid or accrued as dividends on Preferred Stock of the
          Company or any Restricted Subsidiary owned by Persons other than
          the Company and any of its Restricted Subsidiaries; (vi) all
          extraordinary gains and extraordinary losses; and (vii) at the
          irrevocable election of the Company for each occurrence, any net
          after-tax income (loss) from discontinued operations; provided 
                                                                --------
          that for purposes of any subsequent Investment in the entity
          conducting such discontinued operations under Section 4.04, such
          entity shall be treated as an Unrestricted Subsidiary until such
          discontinued operations have actually been disposed of.

               "Adjusted Consolidated Net Tangible Assets" means the total
          amount of assets of the Company and its Restricted Subsidiaries
          (less applicable depreciation, amortization and other valuation
          reserves), except to the extent resulting from write-ups of
          capital assets (excluding write-ups in connection with accounting
          for acquisitions in conformity with GAAP), after deducting
          therefrom (i) all current liabilities of the Company and its
          Restricted Subsidiaries (excluding intercompany items) and (ii)
          all goodwill, trade names, trademarks, patents, unamortized debt
          discount and expense and other like intangibles, all as set forth
          on the most recent quarterly or annual consolidated balance sheet
          of the Company and its Restricted Subsidiaries, prepared in
          conformity with GAAP and filed with the Commission or provided to
          the Trustee pursuant to Section 4.18 hereof.

               "Affiliate" means, as applied to any Person, any other
          Person directly or indirectly controlling, controlled by, or
          under direct or indirect common control with, such Person.  For
          purposes of this definition, "control" (including, with
          correlative meanings, the terms "controlling", "controlled by"
          and "under common control with"), as applied to any Person, means
          the possession, directly or indirectly, of the power to direct or
          cause the direction of the management and policies of such
          Person, whether through the ownership of voting securities, by
          contract or otherwise.

               "Agent" means any Registrar, Paying Agent, authenticating
          agent or co-Registrar.

               "Agent Members" has the meaning provided in Section 2.07(a).

               "Asset Acquisition" means (i) an investment by the Company
          or any of its Restricted Subsidiaries in any other Person
          pursuant to which such Person shall become a Restricted
          Subsidiary or shall be merged into or consolidated with the
          Company or any of its Restricted Subsidiaries or (ii) an
          acquisition by the Company or any of its Restricted Subsidiaries
          of the property and assets of any Person other than the Company
          or any of its Restricted Subsidiaries that constitute
          substantially all of a division or line of business of such
          Person.

               "Asset Sale" means any sale, transfer or other disposition
          (including by way of merger, consolidation or sale-leaseback
          transaction) in one transaction or a series of related
          transactions by the Company or any of its Restricted Subsidiaries
          to any Person other than the Company or any of its Restricted
          Subsidiaries of (i) all or any of the Capital Stock of any
          Restricted Subsidiary, (ii) all or substantially all of the
          property and assets of an operating unit or business of the
          Company or any of its Restricted Subsidiaries or (iii) any other
          property and assets (other than the Capital Stock or other
          Investment in an Unrestricted Subsidiary) of the Company or any
          of its Restricted Subsidiaries outside the ordinary course of
          business of the Company or such Restricted Subsidiary and, in
          each case, that is not governed by the provisions of Article
          Five; provided that "Asset Sale" shall not include (a) sales or 
                --------
          other dispositions of inventory, receivables and other current
          assets, (b) sales or other dispositions of assets for
          consideration at least equal to the fair market value of the
          assets sold or disposed of, to the extent that the consideration
          received would constitute property or assets of the kind
          described in clause (B) of the Section 4.11 hereof, (c) a
          disposition of cash or Temporary Cash Investments, (d) any
          Restricted Payment that is permitted to be made, and is made,
          under Section 4.04, (e) sales or other dispositions of assets
          with a fair market value (as certified in an Officers'
          Certificate) not in excess of $2.0 million (provided that any
          series of related sales or dispositions in excess of $2.0 million
          shall be considered "Asset Sales"), (f) the lease, license,
          transfer of rights-of-use, assignment of a lease, license,
          transfer of rights-of-use or sublease or sublicense of any real
          or personal property in the ordinary course of business, (g)
          foreclosures on assets, (h) substantially simultaneous exchange
          by the Company or any Restricted Subsidiary of property or
          equipment for other property or equipment; provided that the 
                                                     --------
          property or equipment received by the Company or such Restricted
          Subsidiary has, at least substantially equal market value to the
          Company or such Restricted Subsidiary, (i) sales or other
          dispositions by the Company or any Restricted Subsidiary, from
          time to time, of up to 100% of the Southwest Communications
          Business to Central and South West Corporation or its affiliates
          or CSW/ICG ChoiceCom, L.P. and (j) transfer or other disposition
          by the Company or any Restricted Subsidiary of Capital Stock of
          any Restricted Subsidiary or an operating unit or business of the
          Company or any Restricted Subsidiary in exchange for an ownership
          interest in a joint venture whose primary business is related,
          ancillary or complementary to (A) the businesses of the Company
          and its Restricted Subsidiaries at the time of determination or
          (B) the Telecommunications Business; provided that the fair 
                                               --------
          market value of such ownership interest is at least equal to the
          fair market value of such Capital Stock or operating unit or
          business transferred or disposed of (as determined by the Board
          of Directors, where good faith determination shall be conclusive
          and evidenced by a board resolution); and provided further that 
                                                    -------- -------
          the assets or properties so transferred or disposed of pursuant
          to this clause (j) do not exceed 20% of Adjusted Consolidated Net
          Tangible Assets at the time of such transfer or disposition.

               "Average Life" means, at any date of determination with
          respect to any debt security, the quotient obtained by dividing
          (i) the sum of the products of (a) the number of years from such
          date of determination to the dates of each successive scheduled
          principal payment of such debt security and (b) the amount of
          such principal payment by (ii) the sum of all such principal
          payments.

               "Board of Directors" means the Board of Directors of the
          Company as required by the context or any committee of such Board
          of Directors duly authorized to act under this Indenture.

               "Board Resolution" means a copy of a resolution, certified
          by the Secretary or Assistant Secretary of the Company as
          required by the context to have been duly adopted by the Board of
          Directors and to be in full force and effect on the date of such
          certification, and delivered to the Trustee.

               "Business Day" means any day except a Saturday, Sunday or
          other day on which commercial banks in The City of New York, or
          in the city of the Corporate Trust Office of the Trustee, are
          authorized by law to close.

               "Capital Stock" means, with respect to any Person, any and
          all shares, interests, participations or other equivalents
          (however designated, whether voting or non-voting) in equity of
          such Person, whether outstanding on the Closing Date or issued
          thereafter, including, without limitation, all Common Stock,
          Preferred Stock, partnership or membership interests and any
          other right to receive a share of the profits and losses of, or
          distributions of assets of, the issuing Person.

               "Capitalized Lease" means, as applied to any Person, any
          lease of any property (whether real, personal or mixed) of which
          the discounted present value of the rental obligations of such
          Person as lessee, in conformity with GAAP, is required to be
          capitalized on the balance sheet of such Person.

               "Capitalized Lease Obligations" means the amount of the
          liability in respect of a Capitalized Lease that would at such
          time be required to be capitalized and reflected as a liability
          on balance sheet prepared in accordance with GAAP.

               "Change of Control" means such time as (i) a "person" or
          "group" (within the meaning of Sections 13(d) and 14(d)(2) of the
          Exchange Act) becomes the ultimate "beneficial owner" (as defined
          in Rule 13d-3 under the Exchange Act) of (A) more than 40% of the
          total voting power of the Voting Stock of the Company on a fully
          diluted basis and (B) Voting Stock of the Company having a
          greater total voting power than the Voting Stock of the Company
          (on a fully diluted basis) beneficially owned by ICG or (ii)
          individuals who on the Closing Date constitute the Board of
          Directors (together with any new directors whose election by the
          Board of Directors or whose nomination by the Board of Directors
          for election by the Company's stockholders was approved by a vote
          of at least a majority of the members of the Board of Directors
          then in office who either were members of the Board of Directors
          on the Closing Date or whose election or nomination for election
          was previously so approved) cease for any reason to constitute a
          majority of the members of the Board of Directors then in office.

               "Closing Date" means the date on which the Notes are
          originally issued under this Indenture.

               "Commission" means the Securities and Exchange Commission,
          as from time to time constituted, created under the Exchange Act
          or, if at any time after the execution of this instrument such
          Commission is not existing and performing the duties now assigned
          to it under the TIA, then the body performing such duties at such
          time.

               "Common Stock" means, with respect to any Person, any and
          all shares, interests, participations or other equivalents
          (however designated, whether voting or non-voting) of such
          Person's common stock, whether now outstanding or issued after
          the date of this Indenture, including, without limitation, all
          series and classes of such common stock.

               "Company" means the party named as such in the first
          paragraph of this Indenture until a successor replaces it
          pursuant to the applicable provisions of this Indenture and
          thereafter means the successor.

               "Company Order" means a written request or order signed in
          the name of the Company (i) by its Chairman of the Board, the
          Vice Chairman of the Board, its President or a Vice President and
          (ii) by its Chief Financial Officer, Treasurer, an Assistant
          Treasurer, its Secretary or an Assistant Secretary and delivered
          to the Trustee; provided, however, that such written request or 
                          --------  -------
          order may be signed by any two of the officers or directors
          listed in clause (i) above in lieu of being signed by one of such
          officers or directors listed in such clause (i) and one of the
          officers listed in clause (ii) above.

               "Consolidated EBITDA" means, for any period, Adjusted
          Consolidated Net Income for such period plus, to the extent such
          amount was deducted in calculating such Adjusted Consolidated Net
          Income, (i) Consolidated Interest Expense, (ii) income taxes
          (other than income taxes (either positive or negative)
          attributable to extraordinary and non-recurring gains or losses
          or sales of assets), (iii) depreciation expense, (iv)
          amortization expense and (v) all other non-cash items reducing
          Adjusted Consolidated Net Income (other than items that will
          require cash payments and for which an accrual or reserve is, or
          is required by GAAP to be, made), less all non-cash items
          increasing (or, in the case of a loss, decreasing) Adjusted
          Consolidated Net Income, determined, with respect to clauses
          (ii), (iii) and (iv), on a consolidated basis for the Company and
          its Restricted Subsidiaries in conformity with GAAP; provided 
                                                               --------
          that, if any Restricted Subsidiary is not a Wholly Owned
          Restricted Subsidiary, Consolidated EBITDA shall be reduced (to
          the extent not otherwise reduced in accordance with GAAP) by an
          amount equal to (A) the amount of the Adjusted Consolidated Net
          Income attributable to such Restricted Subsidiary multiplied by
          (B) the percentage ownership interest in the income of such
          Restricted Subsidiary not owned on the last day of such period by
          the Company or any of its Restricted Subsidiaries.

               "Consolidated Interest Expense" means, for any period, the
          aggregate amount (without duplication) of interest in respect of
          Indebtedness (including, without limitation, amortization of
          original issue discount on any Indebtedness and the interest
          portion of any deferred payment obligation, calculated in
          accordance with the effective interest method of accounting; all
          commissions, discounts and other fees and charges owed with
          respect to letters of credit and bankers' acceptance financing;
          the net costs associated with Interest Rate Agreements; and
          Indebtedness that is Guaranteed or secured by the Company or any
          of its Restricted Subsidiaries) and the interest component of
          Capitalized Lease Obligations paid, accrued or scheduled to be
          paid or to be accrued by the Company and its Restricted
          Subsidiaries during such period; excluding, however, (i) any 
                                           ---------  -------
          amount of such interest of any Restricted Subsidiary if the net
          income of such Restricted Subsidiary is excluded in the
          calculation of Adjusted Consolidated Net Income pursuant to
          clause (iii) of the definition thereof (but only in the same
          proportion as the net income of such Restricted Subsidiary is
          excluded from the calculation of Adjusted Consolidated Net Income
          pursuant to clause (iii) of the definition thereof) and (ii) any
          premiums, fees and expenses (and any amortization thereof)
          payable in connection with the offering of the Notes, all as
          determined on a consolidated basis (without taking into account
          Unrestricted Subsidiaries) in conformity with GAAP.

               "Consolidated Leverage Ratio" means, on any Transaction
          Date, the ratio of (i) the aggregate amount of Indebtedness of
          the Company and its Restricted Subsidiaries on a consolidated
          basis outstanding on such Transaction Date to (ii) the aggregate
          amount of Consolidated EBITDA for the then most recent four
          fiscal quarters for which financial statements of the Company
          have been filed with the Commission or provided to the Trustee
          pursuant to Section 4.18 hereof (such four fiscal quarter period
          being the "Four Quarter Period"); provided that, in making the 
                     -------------------    --------
          foregoing calculation, pro forma effect shall be given to the
          following events which occur from the beginning of the Four
          Quarter Period through the Transaction Date (the "Reference 
                                                            ---------
          Period"):  (i) the Incurrence of the Indebtedness with respect to
          ------
          which the computation is being made and (if applicable) the
          application of the net proceeds therefrom, including to refinance
          other Indebtedness, as if such Indebtedness was incurred, and the
          application of such proceeds occurred, at the beginning of the
          Four Quarter Period; (ii) the Incurrence, repayment or retirement
          of any other Indebtedness by the Company and its Restricted
          Subsidiaries since the first day of the Four Quarter Period as if
          such Indebtedness was incurred, repaid or retired at the
          beginning of the Four Quarter Period; (iii) in the case of
          Acquired Indebtedness, the related acquisition, as if such
          acquisition occurred at the beginning of the Four Quarter Period;
          (iv) any acquisition or disposition by the Company and its
          Restricted Subsidiaries of any company or any business or any
          assets out of the ordinary course of business, whether by merger,
          stock purchase or sale or asset purchase or sale or any related
          repayment of Indebtedness, in each case since the first day of
          the Four Quarter Period, assuming such acquisition or disposition
          had been consummated on the first day of the Four Quarter Period
          and after giving pro forma effect to net cost savings that the
          Company reasonably believes in good faith could have been
          achieved during the Four Quarter Period as a result of such
          acquisition or disposition (provided that both (A) such cost 
                                      --------
          savings were identified and quantified in an Officers'
          Certificate delivered to the Trustee at the time of the
          consummation of the acquisition or disposition and (B) with
          respect to each acquisition or disposition completed prior to the
          90th day preceding such date of determination, actions were
          commenced or initiated by the Company within 90 days of such
          acquisition or disposition to effect such cost savings identified
          in such Officers' Certificate and with respect to any other
          acquisition or disposition, such Officers' Certificate sets forth
          the specific steps to be taken within the 90 days after such
          acquisition or disposition to accomplish such cost savings); and
          provided further that (x) in making such computation, the 
          -------- -------
          Consolidated Interest Expense attributable to interest on any
          Indebtedness computed on a pro forma basis and (A) bearing a
          floating interest rate shall be computed as if the rate in effect
          on the date of computation had been the applicable rate for the
          entire period and (B) which was not outstanding during the period
          for which the computation is being made but which bears, at the
          option of the Company, a fixed or floating rate of interest shall
          be computed by applying, at the option of the Company, either the
          fixed or floating rate, and (y) in making such computation, the
          Consolidated Interest Expense of the Company attributable to
          interest on any Indebtedness under a revolving credit facility
          computed on a pro forma basis shall be computed based upon the
          pro forma average daily balance of such Indebtedness during the
          applicable period; and (v) the occurrence of any of the events
          described in clauses (i)-(iv) above by any Person that has become
          a Restricted Subsidiary or has been merged with or into the
          Company or any Restricted Subsidiary during such Reference
          Period.

               "Consolidated Net Worth" means, at any date of
          determination, stockholders' equity as set forth on the most
          recently available quarterly or annual consolidated balance sheet
          of the Company and its Restricted Subsidiaries (which shall be as
          of a date not more than 90 days prior to the date of such
          computation, and which shall not take into account Unrestricted
          Subsidiaries), less any amounts attributable to Disqualified
          Stock or any equity security convertible into or exchangeable for
          Indebtedness, the cost of treasury stock and the principal amount
          of any promissory notes receivable from the sale of the Capital
          Stock of the Company or any of its Restricted Subsidiaries, each
          item to be determined in conformity with GAAP (excluding the
          effects of foreign currency exchange adjustments under Financial
          Accounting Standards Board Statement of Financial Accounting
          Standards No. 52).

               "Corporate Trust Office" means the office of the Trustee at
          which the corporate trust business of the Trustee shall, at any
          particular time, be principally administered, which office is, at
          the date of this Indenture, located at 1740 Broadway, Denver,
          Colorado 80274-8693, Attention:  Corporate Trust and Escrow
          Services.

               "Currency Agreement" means any foreign exchange contract,
          currency swap agreement or other similar agreement or
          arrangement.

               "Default" means any event that is, or after notice or
          passage of time or both would be, an Event of Default.

               "Depository" shall mean The Depository Trust Company, its
          nominees, and their respective successors.

               "Disqualified Stock" means any class or series of Capital
          Stock of any Person that by its terms or otherwise is (i)
          required to be redeemed prior to the Stated Maturity of the
          Notes, (ii) redeemable at the option of the holder of such class
          or series of Capital Stock at any time prior to the Stated
          Maturity of the Notes or (iii) convertible into or exchangeable
          for Capital Stock referred to in clause (i) or (ii) above or
          Indebtedness having a scheduled maturity prior to the Stated
          Maturity of the Notes; provided that any Capital Stock that would
                                 --------
          not constitute Disqualified Stock but for provisions thereof
          giving holders thereof the right to require such Person to
          repurchase or redeem such Capital Stock (or the security for
          which such Capital Stock is convertible into or exchangeable for)
          upon the occurrence of an "asset sale" or "change of control"
          occurring prior to the Stated Maturity of the Notes shall not
          constitute Disqualified Stock if the "asset sale" or "change of
          control" provisions applicable to such Capital Stock (or the
          security for which such Capital Stock is convertible into or
          exchangeable for) are no more favorable to the holders of such
          Capital Stock (or the security for which such Capital Stock is
          convertible into or exchangeable for) than the provisions
          contained in Sections 4.11 and 4.12 hereof and such Capital Stock
          (or the security for which such Capital Stock is convertible into
          or exchangeable for) specifically provides that such Person will
          not repurchase or redeem any such stock pursuant to such
          provision prior to the Company's repurchase of such Notes as are
          required to be repurchased pursuant to Sections 4.11 and 4.12
          hereof.

               "Equity Offering" means any public or private sale of
          Capital Stock of the Company (excluding Disqualified Stock),
          other than public offerings with respect to the Company's Common
          Stock registered on Form S-8.

               "Event of Default" has the meaning provided in Section 6.01.

               "Excess Proceeds" has the meaning provided in Section 4.11.

               "Exchange Act" means the Securities Exchange Act of 1934, as
          amended.

               "Exchange Notes" means any notes of the Company containing
          terms identical to the Notes (except that such Exchange Notes (i)
          shall be registered under the Securities Act, (ii) will not
          provide for an increase in the rate of interest (other than with
          respect to overdue amounts) and (iii) will not contain terms with
          respect to transfer restrictions) that are issued and exchanged
          for the Notes pursuant to the Registration Rights Agreement and
          this Indenture.

               "Exchange Offer" means Exchange Offer as defined in the
          Registration Rights Agreement.

               "fair market value" means the price that would be paid in an
          arm's-length transaction between an informed and willing seller
          under no compulsion to sell and an informed and willing buyer
          under no compulsion to buy; fair market value may be determined
          in good faith by the Board of Directors of the Company, whose
          determination shall be conclusive if evidenced by a Board
          Resolution.

               "GAAP" means generally accepted accounting principles in the
          United States of America as in effect as of the Closing Date,
          including, without limitation, those set forth in the opinions
          and pronouncements of the Accounting Principles Board of the
          American Institute of Certified Public Accountants and statements
          and pronouncements of the Financial Accounting Standards Board or
          in such other statements by such other entity as approved by a
          significant segment of the accounting profession.  All ratios and
          computations contained or referred to in the Indenture shall be
          computed in conformity with GAAP applied on a consistent basis,
          except that calculations made for purposes of determining
          compliance with the terms of the covenants and with other
          provisions of the Indenture shall be made without giving effect
          to (i) the amortization of any expenses incurred in connection
          with the offering of the Notes and (ii) except as otherwise
          provided, the amortization of any amounts required or permitted
          by Accounting Principles Board Opinion Nos. 16 and 17.

               "Global Notes" has the meaning provided in Section 2.01.

               "Guarantee" means any obligation, contingent or otherwise,
          of any Person directly or indirectly guaranteeing any
          Indebtedness of any other Person and, without limiting the
          generality of the foregoing, any obligation, direct or indirect,
          contingent or otherwise, of such Person (i) to purchase or pay
          (or advance or supply funds for the purchase or payment of) such
          Indebtedness of such other Person (whether arising by virtue of
          partnership arrangements, or by agreements to keep-well, to
          purchase assets, goods, securities or services, to take-or-pay
          (unless such purchase arrangements or such obligations are on
          arm's length terms and are entered into in the ordinary course of
          business), or to maintain financial statement conditions or
          otherwise) or (ii) entered into for purposes of assuring in any
          other manner the obligee of such Indebtedness of the payment
          thereof or to protect such obligee against loss in respect
          thereof (in whole or in part); provided that the term "Guarantee"
                                         --------
          shall not include endorsements for collection or deposit in the
          ordinary course of business. The term "Guarantee" used as a verb
          has a corresponding meaning.

               "Guaranteed Indebtedness" has the meaning provided in
          Section 4.07.

               "ICG" means ICG Communications, Inc., a Delaware
          corporation.

               "ICG Common Stock" means common stock, par value $.01 per
          share, of ICG.

               "Incur" means, with respect to any Indebtedness, to incur,
          create, issue, assume, Guarantee or otherwise become liable for
          or with respect to, or become responsible for, the payment of,
          contingently or otherwise, such Indebtedness, including an
          "Incurrence" of Acquired Indebtedness; provided that neither the
                                                 --------
          accrual of interest nor the accretion of original issue discount
          shall be considered an Incurrence of Indebtedness.

               "Indebtedness" means, with respect to any Person at any date
          of determination (without duplication), (i) all indebtedness of
          such Person for borrowed money, (ii) all obligations of such
          Person evidenced by bonds, debentures, notes or other similar
          instruments, (iii) all obligations of such Person in respect of
          letters of credit or other similar instruments (including
          reimbursement obligations with respect thereto, but excluding
          trade letters of credit), (iv) all obligations of such Person to
          pay the deferred and unpaid purchase price of property or
          services, which purchase price is due more than six months after
          the date of placing such property in service or taking delivery
          and title thereto or the completion of such services, except
          Trade Payables and accrued current liabilities arising in the
          ordinary course of business, (v) all Capitalized Lease
          Obligations of such Person, (vi) all Indebtedness referred to in
          clauses (i) through (v) hereof of other Persons secured by a Lien
          on any asset of such Person, whether or not such Indebtedness is
          assumed by such Person; provided that the amount of such 
                                  --------
          Indebtedness shall be the lesser of (A) the fair market value of
          such asset at such date of determination and (B) the amount of
          such Indebtedness, (vii) all Indebtedness of other Persons
          Guaranteed by such Person to the extent such Indebtedness is
          Guaranteed by such Person and (viii) to the extent not otherwise
          included in this definition, obligations under Currency
          Agreements and Interest Rate Agreements.  The amount of
          Indebtedness of any Person at any date shall be the outstanding
          balance at such date (or, in the case of a revolving credit or
          other similar facility, the total amount of principal or interest
          outstanding on the date of determination) of all unconditional
          obligations as described above and, with respect to contingent
          obligations, the maximum liability upon the occurrence of the
          contingency giving rise to the obligation of the types described
          above, provided (A) that the amount outstanding at any time of 
                 --------
          any Indebtedness issued with original issue discount is the
          original issue price of such Indebtedness, (B) that money
          borrowed and set aside at the time of the Incurrence of any
          Indebtedness in order to refund the payment of the interest on
          such Indebtedness shall not be deemed to be "Indebtedness" and
          (C) that Indebtedness shall not include any liability for
          federal, state, local or other taxes.

               "Indenture" means this Indenture as originally executed or
          as it may be amended or supplemented from time to time by one or
          more indentures supplemental to this Indenture entered into
          pursuant to the applicable provisions of this Indenture.

               "Institutional Accredited Investor" shall mean an
          institution that is an "accredited investor" as that term is
          defined in Rule 501(a)(1), (2), (3) or (7) under the Securities Act.
          
               "Interest Payment Date" means each semiannual interest
          payment date on February 15 and August 15 of each year,
          commencing August 15, 2003.

               "Interest Rate Agreement" means any interest rate protection
          agreement, interest rate future agreement, interest rate option
          agreement, interest rate swap agreement, interest rate cap
          agreement, interest rate collar agreement, interest rate hedge
          agreement, option or future contract or other similar agreement
          or arrangement.

               "Internet Service Business" means any business operating an
          internet connectivity or internet enhancement service as it
          exists from time to time, including, without limitation, dial-up
          or dedicated internet service, web hosting or collocation
          services, security solutions, the provision and development of
          software in connection therewith, configuration services,
          electronic commerce, intranet solutions, data backup and
          restoral, business, content and collaboration, communications
          tools or network equipment products or services.

               "Investment" means, with respect to any Person, all
          investments by such Person in other Persons in the form of any
          direct or indirect advance, loan or other extension of credit
          (including, without limitation, by way of Guarantee or similar
          arrangement; but excluding installment sales, capital leasing
          arrangements and financings for and advances to customers, in
          each case in the ordinary course of business that are, in
          conformity with GAAP, recorded as assets on the balance sheet of
          the Company or its Restricted Subsidiaries and commissions,
          travel and similar advances to officers and employees made in the
          ordinary course of business) or capital contribution to (by means
          of any transfer of cash or other property to others or any
          payment for property or services for the account or use of
          others), or any purchase or acquisition of Capital Stock, bonds,
          notes, debentures or other similar instruments issued by, such
          other Person and shall include (i) the designation of a
          Restricted Subsidiary as an Unrestricted Subsidiary and (ii) the
          fair market value of the Capital Stock (or any other Investment),
          held by the Company or any of its Restricted Subsidiaries, of (or
          in) any Person that has ceased to be a Restricted Subsidiary,
          including without limitation, by reason of any transaction
          permitted by clause (iii) of the Section 4.06 hereof; provided 
                                                                --------
          that the fair market value of the Investment remaining in any
          Person that has ceased to be a Restricted Subsidiary shall not
          exceed the aggregate amount of Investments previously made in
          such Person valued at the time such Investments were made less
          the net reduction of such Investments; and provided further that
                                                     -------- -------
          any disposition, sale, lease, transfer, license, transfer of
          rights-of-use of, communications equipment, software and capacity
          and/or provision of services, by the Company or any Restricted
          Subsidiary to ICG or its subsidiaries for fair market value (if,
          at the time of such disposition, sale, lease or transfer, the
          Company or such Restricted Subsidiary is a Subsidiary of ICG)
          will not be deemed to be an Investment.  For purposes of the
          definition of "Unrestricted Subsidiary" and Section 4.04 hereof,
          (i) "Investment" shall include the fair market value of the
          assets (net of liabilities (other than liabilities to the Company
          or any of its Restricted Subsidiaries)) of any Restricted
          Subsidiary at the time that such Restricted Subsidiary is
          designated an Unrestricted Subsidiary, (ii) the fair market value
          of the assets (net of liabilities (other than liabilities to the
          Company or any of its Restricted Subsidiaries)) of any
          Unrestricted Subsidiary at the time that such Unrestricted
          Subsidiary is designated a Restricted Subsidiary shall be
          considered a reduction in outstanding Investments and (iii) any
          property transferred to or from an Unrestricted Subsidiary shall
          be valued at its fair market value at the time of such transfer.

               "Investment Grade Securities" means (i) securities issued or
          directly and fully guaranteed or insured by the United States
          government or any agency or instrumentality thereof (other than
          cash equivalents), (ii) debt securities or debt instruments with
          a rating of BBB+ or higher by S&P or Baa1 or higher by Moody's or
          the equivalent of such rating by such rating organization, or, if
          no rating of S&P or Moody's then exists, the equivalent of such
          rating by any other nationally recognized securities rating
          agency, but excluding any debt securities or instruments
          constituting loans or advances among the Company and its
          Subsidiaries, and (iii) investment in any fund that invests
          exclusively in investments of the type described in clauses (i)
          and (ii) which fund may also hold cash pending investment and/or
          distribution.

               "Lien" means any mortgage, pledge, security interest,
          encumbrance, lien or charge of any kind (including, without
          limitation, any conditional sale or other title retention
          agreement or lease in the nature thereof or any agreement to give
          any security interest).

               "Moody's" means Moody's Investors Service, Inc. and its
          successors.

               "Net Cash Proceeds" means (a) with respect to any Asset
          Sale, the proceeds of such Asset Sale in the form of cash or cash
          equivalents, including payments in respect of deferred payment
          obligations (to the extent corresponding to the principal, but
          not interest, component thereof) when received in the form of
          cash or cash equivalents (except to the extent such obligations
          are financed or sold with recourse to the Company or any
          Restricted Subsidiary) and proceeds from the conversion of other
          property received when converted to cash or cash equivalents, net
          of (i) brokerage commissions and other commissions, fees and
          expenses (including fees and expenses of counsel, accountants and
          investment bankers) related to such Asset Sale and any relocation
          expenses incurred as a result thereof, (ii) provisions for all
          taxes (whether or not such taxes will actually be paid or are
          payable) as a result of such Asset Sale without regard to the
          consolidated results of operations of the Company and its
          Restricted Subsidiaries, taken as a whole, (iii) payments made to
          repay Indebtedness or any other obligation outstanding at the
          time of such Asset Sale that either (A) is secured by a Lien on
          the property or assets sold or (B) is required to be paid as a
          result of such sale and (iv) appropriate amounts to be provided
          by the Company or any Restricted Subsidiary as a reserve against
          any liabilities associated with such Asset Sale, including,
          without limitation, pension and other post-employment benefit
          liabilities, liabilities related to environmental matters and
          liabilities under any indemnification obligations associated with
          such Asset Sale, all as determined in conformity with GAAP and
          (b) with respect to any issuance or sale of Capital Stock, the
          proceeds of such issuance or sale in the form of cash or cash
          equivalents, including payments in respect of deferred payment
          obligations (to the extent corresponding to the principal, but
          not interest, component thereof) when received in the form of
          cash or cash equivalents (except to the extent such obligations
          are financed or sold with recourse to the Company or any
          Restricted Subsidiary) and proceeds from the conversion of other
          property received when converted to cash or cash equivalents, net
          of attorney's fees, accountants' fees, underwriters' or placement
          agents' fees, discounts or commissions and brokerage, consultant
          and other fees incurred in connection with such issuance or sale
          and net of taxes paid or payable as a result thereof.

               "Non-U.S. Person" means a Person who is not a U.S. person,
          as defined in Regulation S.

               "Note Amount" has the meaning provided in Section 4.11
          hereof.

               "Note Register" has the meaning provided in Section 2.04.

               "Notes" means any of the notes, as defined in the first
          paragraph of the recitals hereof, that are authenticated and
          delivered under this Indenture.  For all purposes of this
          Indenture, the term "Notes" shall include any Exchange Notes to
          be issued and exchanged for any Notes pursuant to the
          Registration Rights Agreement and this Indenture and, for
          purposes of this Indenture, all Notes and Exchange Notes shall
          vote together as one series of Notes under this Indenture.

               "Offer to Purchase" means an offer to purchase Notes by the
          Company from the Holders commenced by mailing a notice to the
          Trustee and each Holder stating:  (i) the covenant pursuant to
          which the offer is being made and that all Notes validly tendered
          will be accepted for payment on a pro rata basis; (ii) the
          purchase price and the Payment Date; (iii) that any Note not
          tendered will continue to accrue interest pursuant to its terms;
          (iv) that, unless the Company defaults in the payment of the
          purchase price, any Note accepted for payment pursuant to the
          Offer to Purchase shall cease to accrue interest on and after the
          Payment Date; (v) that Holders electing to have a Note purchased
          pursuant to the Offer to Purchase will be required to surrender
          the Note, together with the form entitled "Option of the Holder
          to Elect Purchase" on the reverse side of the Note completed, to
          the Paying Agent at the address specified in the notice prior to
          the close of business on the Business Day immediately preceding
          the Payment Date; (vi) that Holders will be entitled to withdraw
          their election if the Paying Agent receives, not later than the
          close of business on the third Business Day immediately preceding
          the Payment Date, a telegram, facsimile transmission or letter
          setting forth the name of such Holder, the principal amount of
          Notes delivered for purchase and a statement that such Holder is
          withdrawing his election to have such Notes purchased; and (vii)
          that Holders whose Notes are being purchased only in part will be
          issued new Notes equal in principal amount at maturity to the
          unpurchased portion of the Notes surrendered; provided that each
                                                        --------
          Note purchased and each new Note issued shall be in a principal
          amount of $1,000 or an integral multiple thereof.  On the Payment
          Date, the Company shall (i) accept for payment on a pro rata
          basis Notes or portions thereof tendered pursuant to an Offer to
          Purchase; (ii) deposit with the Paying Agent money sufficient to
          pay the purchase price of all Notes or portions thereof so
          accepted; and (iii) deliver, or cause to be delivered, to the
          Trustee all Notes or portions thereof so accepted together with
          an Officers' Certificate specifying the Notes or portions thereof
          accepted for payment by the Company.  The Paying Agent shall
          promptly mail to the Holders of Notes so accepted payment in an
          amount equal to the purchase price (or, if the Notes are
          represented by one or more permanent global Notes registered in
          the name of The Depository Trust Company or its nominee, by such
          other method as required thereby), and the Trustee shall promptly
          authenticate and mail to such Holders a new Note equal in
          principal amount at maturity to any unpurchased portion of the
          Note surrendered; provided that each Note purchased and each new
                             --------
          Note issued shall be in a principal amount at maturity of $1,000
          or an integral multiple thereof.  The Company will publicly
          announce the results of an Offer to Purchase as soon as
          practicable after the Payment Date.  The Trustee shall act as the
          Paying Agent for an Offer to Purchase.  The Company will comply
          with Rule 14e-1 under the Exchange Act and any other securities
          laws and regulations thereunder to the extent such laws and
          regulations are applicable, in the event that the Company is
          required to repurchase Notes pursuant to an Offer to Purchase.

               "Officer" means, with respect to the Company, (i) the
          Chairman of the Board, the Vice Chairman of the Board, the
          President, the Chief Executive Officer, the Chief Financial
          Officer or a Vice President, and (ii) the Treasurer or any
          Assistant Treasurer, or the Secretary or any Assistant Secretary
          of the Company.

               "Officers' Certificate" means a certificate signed by one
          Officer listed in clause (i) of the definition thereof and one
          Officer listed in clause (ii) of the definition thereof;
          provided, however, that any such certificate may be signed by any
          --------  -------
          two of the Officers listed in clause (i) of the definition
          thereof in lieu of being signed by one Officer listed in clause
          (i) of the definition thereof and one Officer listed in clause
          (ii) of the definition thereof.  Each Officers' Certificate
          (other than certificates provided pursuant to TIA Section
          314(a)(4)) shall include the statements provided for in TIA
          Section 314(e).

               "Offshore Certificated Notes" has the meaning provided in
          Section 2.01.

               "Offshore Global Note" has the meaning provided in Section
          2.01.

               "Opinion of Counsel" means a written opinion signed by legal
          counsel who may be an employee of or counsel to the Company. 
          Each such Opinion of Counsel shall include the statements
          provided for in TIA Section 314(e).

               "Paying Agent" has the meaning provided in Section 2.04,
          except that, for the purposes of Article Eight, the Paying Agent
          shall not be the Company or a Subsidiary of the Company or an
          Affiliate of any of them.  The term "Paying Agent" includes any
          additional Paying Agent.

               "Payment Date" means the date of purchase, which shall be a
          Business Day no earlier than 30 days nor later than 60 days from
          the date of notice is mailed pursuant to an Offer to Purchase.

               "Permanent Regulation S Global Notes" means the permanent
          global Notes issued in exchange for one or more Temporary
          Regulation S Global Notes upon certification that the beneficial
          interests in such global Note are owned by either Non-U.S.
          Persons or U.S. Persons who purchased such interests pursuant to
          an exemption from, or in transactions not subject to, the
          registration requirements of the Securities Act.

               "Permitted Investment" means (i) an Investment in the
          Company or a Restricted Subsidiary or a Person which will, upon
          the making of such Investment, become a Restricted Subsidiary or
          be merged or consolidated with or into or transfer or convey all
          or substantially all its assets to, the Company or a Restricted
          Subsidiary; provided that such Person's primary business is 
                      --------
          related, ancillary or complementary to the businesses of the
          Company and its Restricted Subsidiaries on the date of such
          Investment; (ii) Temporary Cash Investments and Investment Grade
          Securities; (iii) payroll, travel and similar advances to cover
          matters that are expected at the time of such advances ultimately
          to be treated as expenses in accordance with GAAP and reasonable
          advances to sales representatives; (iv) any Investment acquired
          by the Company or any of its Restricted Subsidiaries (x) in
          exchange for any other Investment or accounts receivable held by
          the Company or any such Restricted Subsidiary in connection with
          or as a result of a bankruptcy, workout, reorganization or
          recapitalization of the issuer of such other Investment or
          accounts receivable or (y) as a result of a foreclosure by the
          Company or any of its Restricted Subsidiaries with respect to any
          secured Investment or other transfer of title with respect to any
          secured Investment in default; (v) Guarantees permitted by
          Section 4.03 hereof; (vi) loans or advances to employees of the
          Company or any Restricted Subsidiary that do not in the aggregate
          exceed at any one time outstanding $2.0 million; (vii) Currency
          Agreements and Interest Rate Agreements permitted under Section
          4.03; (viii) Investments in prepaid expenses, negotiable
          instruments held for collection and lease, utility deposits and
          workers' compensation, performance and other similar deposits;
          (ix) Investments in debt securities or other evidences of
          Indebtedness that are issued by companies engaged in the
          Telecommunications Business or the Internet Service Business;
          provided that when each Investment pursuant to this clause (ix) 
          --------
          is made, the aggregate amount of Investments outstanding under
          this clause (ix) does not exceed $3.0 million; (x) Strategic
          Investments and Investments in Permitted Joint Ventures in an
          amount not to exceed $30.0 million at any one time outstanding;
          (xi) an Investment in any Person the primary business of which is
          related, ancillary or complementary to (I) the business of the
          Company and its Subsidiaries on the date of such Investments or
          (II) the Telecommunications Business in an amount not to exceed
          at any time outstanding the sum of (A) $20.0 million plus (B) 10%
          of the Company's Consolidated EBITDA, if positive, for the
          immediately preceding four fiscal quarters (valued in each case
          as provided in the definition of "Investments"); (xii) securities
          received in connection with Asset Sales to the extent
          constituting non-cash consideration permitted under Section 4.11
          hereof; (xiii) stock, obligations or securities received in
          satisfaction of judgments, bankruptcies, workouts or settlements;
          (xiv) Investments in CSW/ICG ChoiceCom, L.P.; and (xv) any
          Investments acquired as capital contribution, including without
          limitation, acquisition of shares of ICG Common Stock.

               "Permitted Joint Venture" means any Unrestricted Subsidiary
          or any other Person in which the Company or a Restricted
          Subsidiary owns, directly or indirectly, an ownership interest
          (other than a Restricted Subsidiary) and whose primary business
          is related, ancillary or complementary to (i) the businesses of
          the Company and its Restricted Subsidiaries at the time of
          determination or (ii) the Telecommunications Business.

               "Permitted Liens" means (i) Liens for taxes, assessments,
          governmental charges or claims that are being contested in good
          faith by appropriate legal proceedings promptly instituted and
          diligently conducted and for which a reserve or other appropriate
          provision, if any, as shall be required in conformity with GAAP
          shall have been made; (ii) statutory and common law Liens of
          landlords and carriers, warehousemen, mechanics, attorneys,
          suppliers, materialmen, repairmen or other similar Liens arising
          in the ordinary course of business, unexercised rights of set
          off, in each case with respect to amounts not yet delinquent or
          that are bonded or being contested in good faith by appropriate
          legal proceedings promptly instituted and diligently conducted
          and for which a reserve or other appropriate provision, if any,
          as shall be required in conformity with GAAP shall have been
          made; (iii) Liens incurred or deposits made in the ordinary
          course of business in connection with workers' compensation,
          unemployment insurance and other types of social security; (iv)
          Liens incurred or deposits made to secure the performance of
          tenders, bids, leases, licenses, statutory or regulatory
          obligations, bankers' acceptances, surety, performance and appeal
          bonds, trade or government contracts, performance and return-of-
          money bonds and other obligations of a similar nature incurred in
          the ordinary course of business (exclusive of obligations for the
          payment of borrowed money); (v) easements (including reciprocal
          easement agreements), rights-of-way, municipal, building and
          zoning ordinances and similar charges, utility agreements,
          covenants, reservations, restrictions, encroachments, charges,
          encumbrances, title defects or other irregularities that do not
          materially interfere with the ordinary course of business of the
          Company or any of its Restricted Subsidiaries; (vi) Liens
          (including extensions and renewals thereof) upon real or personal
          property or other assets or rights acquired after the Closing
          Date; provided that (a) such Lien is created solely for the 
                --------
          purpose of securing Trade Payables that the Company reasonably
          expects to pay within 180 days or Indebtedness Incurred, in
          accordance with Section 4.03, to finance the cost of (including
          the cost of design, development, acquisition, construction,
          installment, improvements, transportation or integration) or to
          acquire the item of property or assets subject thereto
          (including, without limitation, acquisition by way of
          acquisitions of real property, leasehold improvements, licenses,
          rights-of-use, Capitalized Leases and installment sales, and any
          refinancings thereof) and such Lien is created prior to, at the
          time of or within six months after the later of the acquisition,
          the completion of construction or the commencement of full
          operation of such property, (b) the principal amount of the Trade
          Payables or Indebtedness secured by such Lien does not exceed
          100% of such cost and (c) any such Lien shall not extend to or
          cover any property or assets other than such item of property or
          assets and any improvements on such item; (vii) leases,
          subleases, licenses and rights-of-use granted to others and
          rights of purchase pursuant to installment sales that do not
          materially interfere with the ordinary course of business of the
          Company and its Restricted Subsidiaries, taken as a whole; (viii)
          Liens encumbering property or assets under construction arising
          from progress or partial payments by a customer of the Company or
          its Restricted Subsidiaries relating to such property or assets;
          (ix) any interest or title of a lessor in the property subject to
          any Capitalized Lease or operating lease; (x) Liens arising from
          filing Uniform Commercial Code financing statements regarding
          leases or installment sales; (xi) Liens on property of, or on
          shares of Capital Stock or Indebtedness of, any Person existing
          at the time such Person becomes, or becomes a part of, any
          Restricted Subsidiary; provided that such Liens do not extend to
                                 --------
          or cover any property or assets of the Company or any Restricted
          Subsidiary other than the property or assets acquired; (xii)
          Liens in favor of the Company or any Restricted Subsidiary;
          (xiii) Liens arising from the rendering of a final judgment or
          order against the Company or any Restricted Subsidiary that does
          not give rise to an Event of Default; (xiv) Liens securing
          reimbursement obligations with respect to letters of credit that
          encumber documents and other property relating to such letters of
          credit and the products and proceeds thereof; (xv) Liens in favor
          of customs and revenue authorities arising as a matter of law to
          secure payment of customs duties in connection with the
          importation of goods; (xvi) Liens encumbering customary initial
          deposits and margin deposits, and other Liens that are within the
          general parameters customary in the industry and incurred in the
          ordinary course of business, in each case, securing Indebtedness
          under Interest Rate Agreements and Currency Agreements and
          forward contracts, options, future contracts, futures options or
          similar agreements or arrangements designed solely to protect the
          Company or any of its Restricted Subsidiaries from fluctuations
          in interest rates, currencies or the price of commodities; (xvii)
          Liens arising out of conditional sale, installment sales, title
          retention, consignment or similar arrangements for the sale of
          goods entered into by the Company or any of its Restricted
          Subsidiaries in the ordinary course of business; and (xviii)
          Liens on or sales of receivables.

               "Person" means an individual, a corporation, a partnership,
          a limited liability company, a joint venture, an association, a
          trust, an unincorporated organization or any other entity or
          organization, including a government or political subdivision or
          an agency or instrumentality thereof.

               "Preferred Stock" or "preferred stock" means, with respect
          to any Person, any and all shares, interests, participation or
          other equivalents (however designated, whether voting or non-
          voting) of such Person's preferred or preference stock, whether
          now outstanding or issued after the date of this Indenture,
          including, without limitation, all series and classes of such
          preferred or preference stock.

               "principal" of a debt security, including the Notes, means
          the principal amount due on the Stated Maturity as shown on such
          debt security.

               "Private Placement Legend" means the legend initially set
          forth on the Notes in the form set forth in Section 2.02(a).

               "QIB" means a "qualified institutional buyer" as defined in
          Rule 144A.

               "Redemption Date", when used with respect to any Note or
          part thereof to be redeemed, means the date fixed for such
          redemption by or pursuant to the terms of the Notes and this
          Indenture.

               "Redemption Price", when used with respect to any Note or
          part thereof to be redeemed, means the price at which such Note
          is to be redeemed pursuant to the terms of the Notes and this
          Indenture.

               "Registrar" has the meaning provided in Section 2.04.

               "Registration" has the meaning provided in Section 4.18.

               "Registration Rights Agreement" means the Registration
          Rights Agreement, dated February 12, 1998, between the Company
          and Morgan Stanley & Co. Incorporated relating to the Notes.

               "Registration Statement" means any registration statement of
          the Company that covers any of the Exchange Notes, and all
          amendments and supplements to any such Registration Statement,
          including post-effective amendments, in each case including the
          prospectus contained therein, all exhibits thereto and all
          material incorporated by reference therein.

               "Regular Record Date" for the interest payable on any
          Interest Payment Date means the February 1 or August 1 (whether
          or not a Business Day), as the case may be, next preceding such
          Interest Payment Date.

               "Regulation S" means Regulation S under the Securities Act.

               "Responsible Officer", when used with respect to the
          Trustee, means the chairman or any vice chairman of the board of
          directors, the chairman or any vice chairman of the executive
          committee of the board of directors, the chairman of the trust
          committee, the president, any vice president, any assistant vice
          president, the secretary, any assistant secretary, the treasurer,
          any assistant treasurer, the cashier, any assistant cashier, any
          trust officer or assistant trust officer, the controller or any
          assistant controller or any other officer of the Trustee
          customarily performing functions similar to those performed by
          any of the above designated officers and also means, with respect
          to a particular corporate trust matter, any other officer to whom
          such matter is referred because of his or her knowledge of and
          familiarity with the particular subject.

               "Restricted Payments" has the meaning provided in Section
          4.04.

               "Restricted Subsidiary" means any Subsidiary of the Company
          other than an Unrestricted Subsidiary.

               "Rule 144A" means Rule 144A under the Securities Act.

               "S&P" means Standard & Poor's Ratings Services and its
          successors.

               "Securities Act" means the Securities Act of 1933, as
          amended.

               "Shelf Registration Statement" means Shelf Registration
          Statement as defined in the Registration Rights Agreement.

               "Significant Subsidiary" means, at any date of
          determination, any Restricted Subsidiary that, together with its
          Subsidiaries, (i) for the most recent fiscal year of the Company,
          accounted for more than 10% of the consolidated revenues of the
          Company and its Restricted Subsidiaries or (ii) as of the end of
          such fiscal year, was the owner of more than 10% of the
          consolidated assets of the Company and its Restricted
          Subsidiaries, all as set forth on the most recently available
          consolidated financial statements of the Company for such fiscal
          year.

               "Southwest Communications Business" means the Company's or
          any of its Subsidiaries' (A) Internet connectivity or Internet
          enhancement service as it exists from time to time in the states
          of Texas, Louisiana, Arkansas and Oklahoma, including, without
          limitation, dial-up or dedicated Internet service, Web site
          hosting or collocation services, security solutions, the
          provision and development of software in connection therewith,
          configuration services, electronic commerce, intranet solutions,
          data backup and restoral, business content and collaboration,
          communications tools or network equipment products or services
          and (B) development, ownership or operations of one or more
          telephone, telecommunications or information systems or the
          provision of telephony, telecommunications or information
          services (including, without limitation, any voice, video, data
          or Internet services) and any related, ancillary or complementary
          business in the states of Texas, Louisiana, Arkansas and
          Oklahoma.

               "Specified Date" means any Redemption Date, any Payment Date
          for an Offer to Purchase or any date on which the Notes first
          become due and payable after an Event of Default.

               "Stated Maturity" means (i) with respect to any debt
          security, the date specified in such debt security as the fixed
          date on which the final installment of principal of such debt
          security is due and payable and (ii) with respect to any
          scheduled installment of principal of or interest on any debt
          security, the date specified in such debt security as the fixed
          date on which such installment is due and payable.

               "Strategic Investments" means (A) Investments that the Board
          of Directors has determined in good faith will enable the Company
          or any of its Restricted Subsidiaries to obtain additional
          business that it might not be able to obtain without making such
          Investment and (B) Investments in entities the principal function
          of which is to perform research and development with respect to
          products and services that may be used or useful in the
          Telecommunications Business or the Internet Service Business;
          provided that the Company or one of its Restricted Subsidiaries 
          --------
          is entitled or otherwise reasonably expected to obtain rights to
          such products or services as a result of such Investment.

               "Strategic Subordinated Indebtedness" means Indebtedness of
          the Company that (i) is expressly made subordinate in right of
          payment to the Notes and (ii) provides that no payment of
          principal, premium or interest on, or any other payment with
          respect to, such Indebtedness may be made prior to the payment in
          full of all of the Company's obligations under the Notes.

               "Subsidiary" means, with respect to any Person, (i) any
          corporation, association, or other business entity (other than a
          partnership) of which more than 50% of the total voting power of
          shares of Capital Stock entitled (without regard to the
          occurrence of any contingency) to vote in the election of
          directors, managers or trustees thereof is at the time of
          determination owned or controlled, directly or indirectly, by
          such Person or one or more of the other Subsidiaries of such
          Person or a combination thereof and (ii) any partnership, joint
          venture, limited liability company or similar entity of which (x)
          more than 50% of the capital accounts, distribution rights, total
          equity and voting interests or general or limited partnership
          interests, as applicable, are owned or controlled, directly or
          indirectly, by such Person or one or more of the other
          Subsidiaries of such Person or a combination thereof whether in
          the form of membership, general, special or limited partnership
          or otherwise and (y) such Person or any Wholly Owned Restricted
          Subsidiary of such Person is a general partner or otherwise
          controls such entity.

               "Telecommunications Business" means the development,
          ownership or operation of one or more telephone,
          telecommunications or information systems or the provision of
          telephony, telecommunications or information services (including,
          without limitation, any voice, video, data or Internet services)
          and any related, ancillary or complementary business.

               "Temporary Cash Investment" means any of the following:  (i)
          direct obligations of the United States of America or any agency
          thereof or obligations fully and unconditionally guaranteed by
          the United States of America or any agency or instrumentality
          thereof, (ii) deposit accounts, time deposit accounts,
          certificates of deposit, eurodollar time deposits, overnight bank
          deposits and money market deposits maturing within one year or
          less of the date of acquisition thereof issued by a bank or trust
          company which is organized under the laws of the United States of
          America, any state thereof or any foreign country recognized by
          the United States of America, and which bank or trust company has
          capital, surplus and undivided profits aggregating in excess of
          $50 million (or the foreign currency equivalent thereof) and has
          outstanding debt which is rated "A" (or such similar equivalent
          rating) or higher by at least one nationally recognized
          statistical rating organization (as defined in Rule 436 under the
          Securities Act) or any money-market fund sponsored by a
          registered broker dealer or mutual fund distributor, (iii)
          repurchase obligations with a term of not more than 30 days for
          underlying securities of the types described in clauses (i) and
          (ii) above entered into with a bank meeting the qualifications
          described in clause (ii) above, (iv) commercial paper, maturing
          not more than 90 days after the date of acquisition, issued by a
          corporation (other than an Affiliate of the Company) organized
          and in existence under the laws of the United States of America,
          any state thereof or any foreign country recognized by the United
          States of America with a rating at the time as of which any
          investment therein is made of "P-1" (or higher) according to
          Moody's or "A-1" (or higher) according to S&P, (v) securities
          with maturities of six months or less from the date of
          acquisition issued or fully and unconditionally guaranteed by any
          state, commonwealth or territory of the United States of America,
          or by any political subdivision or taxing authority thereof, and
          rated at least "A" by S&P or Moody's, and (vi) investment funds
          investing 95% of their assets in securities of the type described
          in clauses (i) through (v) above.

               "Temporary Regulation S Global Note" means the Global Note
          bearing the Private Placement Legend in bearer form without
          interest coupons, that will be issued in a denomination equal to
          the outstanding principal amount of the Notes sold in reliance on
          Regulation S and deposited with the Trustee, as custodian for the
          Depository.

               "TIA" or "Trust Indenture Act" means the Trust Indenture Act
          of 1939, as amended (15 U.S. Code SS. 77aaa-77bbb), as in effect
          on the date this Indenture was executed, except as provided in
          Section 9.06; provided, however, that, in the event the Trust 
                        --------  -------
          Indenture Act of 1939 is amended after such date, "TIA" or "Trust
          Indenture Act" means, to the extent required by any such
          amendment, the Trust Indenture Act of 1939 as so amended.

               "Trade Payables" means, with respect to any Person, any
          accounts payable or any other indebtedness or monetary obligation
          to trade creditors created, assumed or Guaranteed by such Person
          or any of its Subsidiaries arising in the ordinary course of
          business in connection with the acquisition of goods or services
          and required to be paid within one year.

               "Transaction Date" means, with respect to the Incurrence of
          any Indebtedness by the Company or any of its Restricted
          Subsidiaries, the date such Indebtedness is to be Incurred and,
          with respect to any Restricted Payment, the date such Restricted
          Payment is to be made.

               "Trustee" means the party named as such in the first
          paragraph of this Indenture until a successor replaces it in
          accordance with the provisions of Article Seven of this Indenture
          and thereafter means such successor.

               "United States Bankruptcy Code" means the Bankruptcy Reform
          Act of 1978, as amended and as codified in Title 11 of the United
          States Code, as amended from time to time hereafter, or any
          successor federal bankruptcy law.

               "Unrestricted Subsidiary" means (i) any Subsidiary of the
          Company that at the time of determination shall be designated an
          Unrestricted Subsidiary by the Board of Directors in the manner
          provided below; and (ii) any Subsidiary of an Unrestricted
          Subsidiary. The Board of Directors may designate any Restricted
          Subsidiary (including any newly acquired or newly formed
          Subsidiary of the Company) to be an Unrestricted Subsidiary
          unless such Subsidiary owns any Capital Stock of, or owns or
          holds any Lien on any property of, the Company or any Restricted
          Subsidiary; provided that (A) any Guarantee by the Company or any
                      --------
          Restricted Subsidiary of any Indebtedness of the Subsidiary being
          so designated shall be deemed an "Incurrence" of such
          Indebtedness and an "Investment" by the Company or such
          Restricted Subsidiary (or both, if applicable) at the time of
          such designation; (B) either (I) the Subsidiary to be so
          designated has total assets of $1,000 or less or (II) if such
          Subsidiary has assets greater than $1,000, such designation would
          be permitted under Section 4.04 and (C) if applicable, the
          Incurrence of Indebtedness and the Investment referred to in
          clause (A) of this proviso would be permitted under Sections 4.03
          and 4.04.  The Board of Directors may designate any Unrestricted
          Subsidiary to be a Restricted Subsidiary; provided that (i) no 
                                                    --------
          Default or Event of Default shall have occurred and be continuing
          at the time of or after giving effect to such designation and
          (ii) all Liens and Indebtedness of such Unrestricted Subsidiary
          outstanding immediately after such designation would, if Incurred
          at such time, have been permitted to be Incurred (and shall be
          deemed to have been Incurred) for all purposes of this Indenture. 
          Any such designation by the Board of Directors shall be evidenced
          to the Trustee by promptly filing with the Trustee a copy of the
          Board Resolution giving effect to such designation and an
          Officers' Certificate certifying that such designation complied
          with the foregoing provisions.

               "U.S. Certificated Notes" has the meaning provided in
          Section 2.01.

               "U.S. Global Note" has the meaning provided in Section 2.01.

               "U.S. Government Obligations" means securities that are (i)
          direct obligations of the United States of America for the
          payment of which its full faith and credit is pledged or (ii)
          obligations of a Person controlled or supervised by and acting as
          an agency or instrumentality of the United States of America the
          payment of which is unconditionally guaranteed as a full faith
          and credit obligation by the United States of America, which, in
          either case, are not callable or redeemable at the option of the
          issuer thereof at any time prior to the Stated Maturity of the
          Notes, and shall also include depository receipts issued by a
          bank or trust company as custodian with respect to any such U.S.
          Government Obligation or a specific payment of interest on or
          principal of any such U.S. Government Obligation held by such
          custodian for the account of the holder of a depository receipt;
          provided that (except as required by law) such custodian is not 
          --------
          authorized to make any deduction from the amount payable to the
          holder of such depository receipt from any amount received by the
          custodian in respect of the U.S. Government Obligation or the
          specific payment of interest on or principal of the U.S.
          Government Obligation evidenced by such depository receipt.

               "U.S. Person" has the meaning ascribed thereto in Rule 902
          under the Securities Act.

               "Voting Stock" means, with respect to any Person, Capital
          Stock of any class or kind ordinarily having the power to vote
          for the election of directors, managers or other voting members
          of the governing body of such Person.

               "Wholly Owned" means, with respect to any Subsidiary of any
          Person, the ownership of all of the outstanding Capital Stock of
          such Subsidiary (other than any director's qualifying shares or
          Investments by foreign nationals mandated by applicable law) by
          such Person or one or more Wholly Owned Subsidiaries of such
          Person.

                    SECTION 1.02.  Incorporation by Reference of Trust 
                                   -----------------------------------
          Indenture Act.  Whenever this Indenture refers to a provision of
          -------------
          the TIA, the provision is incorporated by reference in and made a
          part of this Indenture.  The following TIA terms used in this
          Indenture have the following meanings:

                    "indenture securities" means the Notes;

                    "indenture security holder" means a Holder or a
               Noteholder;

                    "indenture to be qualified" means this Indenture;

                    "indenture trustee" or "institutional trustee" means
               the Trustee; and

                    "obligor" on the indenture securities means the Company
               or any other obligor on the Notes.

                    All other TIA terms used in this Indenture that are
          defined by the TIA, defined by TIA reference to another statute
          or defined by a rule of the Commission and not otherwise defined
          herein have the meanings assigned to them therein.

                    SECTION 1.03.  Rules of Construction.  Unless the 
                                   ---------------------
          context otherwise requires:

                    (i)    a term has the meaning assigned to it;

                    (ii)   an accounting term not otherwise defined has the
               meaning assigned to it in accordance with GAAP;

                    (iii)  "or" is not exclusive;

                    (iv)   words in the singular include the plural, and
               words in the plural include the singular;

                    (v)    provisions apply to successive events and
               transactions;

                    (vi)   "herein," "hereof" and other words of similar
               import refer to this Indenture as a whole and not to any
               particular Article, Section or other subdivision; and

                    (vii)  all references to Sections or Articles refer to
               Sections or Articles of this Indenture unless otherwise
               indicated.


                                     ARTICLE TWO
                                      THE NOTES

                    SECTION 2.01.  Form and Dating.  The Notes and the 
                                   ---------------
          Trustee's certificate of authentication shall be substantially in
          the form annexed hereto as Exhibit A.  The Notes may have such
          appropriate insertions, omissions, substitutions and other
          variations as are required or permitted by this Indenture and may
          have letters, notations, legends or endorsements required by law,
          stock exchange agreements to which the Company is subject or
          usage.  Any portion of the text of any Note may be set forth on
          the reverse thereof, with an appropriate reference thereto on the
          face of the Note.  The Company shall approve the form of the
          Notes and any notation, legend or endorsement on the Notes.  Each
          Note shall be dated the date of its authentication.

                    The terms and provisions contained in the form of the
          Notes annexed hereto as Exhibit A shall constitute, and are
          hereby expressly made, a part of this Indenture.  Each of the
          Company and the Trustee, by its execution and delivery of this
          Indenture, expressly agrees to the terms and provisions of the
          Notes applicable to it and to be bound thereby.

                    Notes offered and sold in reliance on Rule 144A shall
          be issued initially in the form of one or more permanent global
          Notes in registered form, substantially in the form set forth in
          Exhibit A (the "U.S. Global Note"), deposited with the Trustee, 
                          ----------------
          as custodian for the Depository, duly executed by the Company and
          authenticated by the Trustee as hereinafter provided.  The
          aggregate principal amount at maturity of a U.S. Global Note may
          from time to time be increased or decreased by adjustments made
          on the records of the Trustee, as custodian for the Depository or
          its nominee, as hereinafter provided.

                    Notes offered and sold in offshore transactions in
          reliance on Regulation S shall be issued initially in the form of
          one or more temporary global Notes in registered form
          substantially in the form set forth in Exhibit A (the "Temporary
                                                                 ---------
          Regulation S Global Note"), deposited on behalf of the purchasers
          ------------------------
          of the Notes represented thereby with the Trustee, as custodian
          for the Depository, duly executed by the Company and
          authenticated by the Trustee as hereinafter provided.  At any
          time following March 24, 1998 upon receipt by the Trustee and the
          Company of a certificate substantially in the form of Exhibit B
          hereto, one or more permanent global Notes in registered form
          substantially in the form set forth in Exhibit A (the "Permanent
                                                                 ---------
          Regulation S Global Note" and together with the Temporary 
          ------------------------
          Regulation S Global Note, the "Offshore Global Note") duly 
                                         --------------------
          executed by the Company and authenticated by the Trustee as
          hereinafter provided shall be deposited with the Trustee, as
          custodian for the Depository, which shall reflect on its books
          and records the date and a decrease in the principal amount of
          the Temporary Regulation S Global Notes in an amount equal to the
          principal amount of the beneficial interest in the Temporary
          Regulation S Global Notes transferred.  The aggregate principal
          amount at maturity of an Offshore Global Note may from time to
          time be increased or decreased by adjustments made in the records
          of the Trustee, as custodian for the Depository or its nominee,
          as herein provided.

                    Notes offered and sold to Institutional Accredited
          Investors which are not QIBs (excluding Non-U.S. Persons) shall
          be issued in the form of permanent certificated Notes in
          registered form in substantially the form set forth in Exhibit A
          (the "U.S. Certificated Notes").  Notes issued pursuant to 
                -----------------------
          Section 2.07 in exchange for interests in the Offshore Global
          Note shall be in the form of certificated Notes in registered
          form substantially in the form set forth in Exhibit A (the
          "Offshore Certificated Notes").  Notes issued pursuant to 
           ---------------------------
          Section 2.07 in exchange for interests in the U.S. Global Note
          shall be in the form of the U.S. Certificated Note.

                    The Offshore Certificated Notes and the U.S.
          Certificated Notes are sometimes collectively referred to herein
          as the "Certificated Notes".  The U.S. Global Notes and Offshore
                  ------------------
          Global Notes are sometimes collectively herein referred to as the
          "Global Notes".
           ------------

                    The definitive Notes shall be typed, printed,
          lithographed or engraved or produced by any combination of these
          methods or may be produced in any other manner permitted by the
          rules of any securities exchange on which the Notes may be
          listed, all as determined by the officers executing such Notes,
          as evidenced by their execution of such Notes.

                    SECTION 2.02.  Restrictive Legends.  (a)  Note Legends. 
                                   -------------------        ------------
          Unless and until a Note is exchanged for an Exchange Note or
          otherwise disposed of in connection with an effective
          Registration Statement pursuant to the Registration Rights
          Agreement, (i) each U.S. Global Note and each U.S. Certificated
          Note shall bear the legend, set forth below on the face thereof
          and (ii) each Offshore Certificated Note and each Temporary
          Regulation S Global Note shall bear the legend set forth below on
          the face thereof until at least 41 days after the Closing Date
          and receipt by the Company and the Trustee of a certificate
          substantially in the form of Exhibit B hereto.

               THIS NOTE HAS NOT BEEN REGISTERED UNDER THE U.S. SECURITIES
               ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), OR ANY STATE
               SECURITIES LAWS, AND ACCORDINGLY, MAY NOT BE OFFERED, SOLD, 
               PLEDGED OR OTHERWISE TRANSFERRED WITHIN THE UNITED STATES OR
               TO, OR FOR THE ACCOUNT OR BENEFIT OF, U.S. PERSONS EXCEPT AS
               SET FORTH IN THE FOLLOWING SENTENCE.  BY ITS ACQUISITION
               HEREOF, THE HOLDER (1) REPRESENTS THAT (A) IT IS A
               "QUALIFIED INSTITUTIONAL BUYER" (AS DEFINED IN RULE 144A
               UNDER THE SECURITIES ACT) OR (B) IT IS AN INSTITUTIONAL
               "ACCREDITED INVESTOR" (AS DEFINED IN RULE 501(a)(1), (2),
               (3) OR (7) OF REGULATION D UNDER THE SECURITIES ACT) (AN
               "INSTITUTIONAL ACCREDITED INVESTOR") OR (C) IT IS NOT A U.S.
               PERSON AND IS ACQUIRING THIS NOTE IN AN OFFSHORE TRANSACTION
               IN COMPLIANCE WITH REGULATION S UNDER THE SECURITIES ACT;
               (2) AGREES THAT IT WILL NOT, WITHIN THE TIME PERIOD REFERRED
               TO IN RULE 144(k) (TAKING INTO ACCOUNT THE PROVISIONS OF
               RULE 144(d) UNDER THE SECURITIES ACT, IF APPLICABLE), RESELL
               OR OTHERWISE TRANSFER THIS NOTE EXCEPT (A) TO THE COMPANY OR
               ANY SUBSIDIARY THEREOF, (B) TO A QUALIFIED INSTITUTIONAL
               BUYER IN COMPLIANCE WITH RULE 144A UNDER THE SECURITIES ACT,
               (C) INSIDE THE UNITED STATES TO AN INSTITUTIONAL ACCREDITED
               INVESTOR THAT, PRIOR TO SUCH TRANSFER, FURNISHES TO THE
               TRUSTEE A SIGNED LETTER CONTAINING CERTAIN REPRESENTATIONS
               AND AGREEMENTS RELATING TO THE RESTRICTIONS ON TRANSFER OF
               THIS NOTE (THE FORM OF WHICH LETTER CAN BE OBTAINED FROM THE
               TRUSTEE) AND IF SUCH TRANSFER IS IN RESPECT OF AN AGGREGATE
               ACCRETED VALUE OF NOTES AT THE TIME OF TRANSFER OF LESS THAN
               $250,000 AN OPINION OF COUNSEL ACCEPTABLE TO THE COMPANY
               THAT SUCH TRANSFER IS IN COMPLIANCE WITH THE SECURITIES ACT,
               (D) OUTSIDE THE UNITED STATES IN AN OFFSHORE TRANSACTION IN
               COMPLIANCE WITH RULE 904 UNDER THE SECURITIES ACT,
               (E) PURSUANT TO THE EXEMPTION FROM REGISTRATION PROVIDED BY
               RULE 144 UNDER THE SECURITIES ACT (IF AVAILABLE) OR
               (F) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER
               THE SECURITIES ACT AND (3) AGREES THAT IT WILL DELIVER TO
               EACH PERSON TO WHOM THIS NOTE IS TRANSFERRED A NOTICE
               SUBSTANTIALLY TO THE EFFECT OF THIS LEGEND.  IN CONNECTION
               WITH ANY TRANSFER OF THIS NOTE WITHIN THE TIME PERIOD
               REFERRED TO ABOVE, THE HOLDER MUST CHECK THE APPROPRIATE BOX
               SET FORTH ON THE REVERSE HEREOF RELATING TO THE MANNER OF
               SUCH TRANSFER AND SUBMIT THIS CERTIFICATE TO THE TRUSTEE. 
               IF THE PROPOSED TRANSFEREE IS AN INSTITUTIONAL ACCREDITED
               INVESTOR, THE HOLDER MUST, PRIOR TO SUCH TRANSFER, FURNISH
               TO EACH OF THE TRUSTEE AND THE COMPANY SUCH CERTIFICATIONS,
               LEGAL OPINIONS OR OTHER INFORMATION AS SUCH PERSONS MAY
               REASONABLY REQUIRE TO CONFIRM THAT SUCH TRANSFER IS BEING
               MADE PURSUANT TO AN EXEMPTION FROM, OR IN A TRANSACTION NOT
               SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES
               ACT.  AS USED HEREIN, THE TERMS "OFFSHORE TRANSACTION,"
               "UNITED STATES" AND "U.S. PERSON" HAVE THE MEANINGS GIVEN TO
               THEM BY REGULATION S UNDER THE SECURITIES ACT.  THE
               INDENTURE CONTAINS A PROVISION REQUIRING THE TRUSTEE TO
               REFUSE TO REGISTER ANY TRANSFER OF THIS NOTE IN VIOLATION OF
               THE FOREGOING RESTRICTIONS.

                    (b)    Global Note Legend.  Each Global Note, whether 
                           ------------------
          or not an Exchange Note, shall also bear the following legend on
          the face thereof:

               UNLESS THIS GLOBAL NOTE IS PRESENTED BY AN AUTHORIZED
               REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY TO THE
               COMPANY OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE
               OR PAYMENT, AND ANY NOTE ISSUED IS REGISTERED IN THE NAME OF
               CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN
               AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY OR
               SUCH OTHER REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY OR
               SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED
               REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY (AND ANY
               PAYMENT HEREON IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY
               AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF THE
               DEPOSITORY TRUST COMPANY), ANY TRANSFER, PLEDGE OR OTHER USE
               HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS
               WRONGFUL SINCE THE REGISTERED OWNER HEREOF, CEDE & CO., HAS
               AN INTEREST HEREIN.

               TRANSFERS OF THIS GLOBAL NOTE SHALL BE LIMITED TO TRANSFERS
               IN WHOLE, BUT NOT IN PART, TO NOMINEES OF CEDE & CO. OR TO A
               SUCCESSOR THEREOF OR SUCH SUCCESSOR'S NOMINEE AND TRANSFERS
               OF PORTIONS OF THIS GLOBAL NOTE SHALL BE LIMITED TO
               TRANSFERS MADE IN ACCORDANCE WITH THE RESTRICTIONS SET FORTH
               IN SECTION 2.08 OF THE INDENTURE.

                    SECTION 2.03.  Execution, Authentication and 
                                   -----------------------------
          Denominations.  Subject to Article Four, the aggregate principal
          -------------
          amount at maturity of Notes (including Exchange Notes) which may
          be authenticated and delivered under this Indenture is unlimited. 
          The Notes shall be executed by two Officers of the Company, by
          facsimile or manual signature, in the name and on behalf of the
          Company.

                    If an Officer whose signature is on a Note no longer
          holds that office at the time the Trustee or authenticating agent
          authenticates the Note, the Note shall be valid nevertheless.

                    A Note shall not be valid until the Trustee or
          authenticating agent manually signs the certificate of
          authentication on the Note.  The signature shall be conclusive
          evidence that the Note has been authenticated under this
          Indenture.

                    At any time and from time to time after the execution
          of this Indenture, the Trustee or an authenticating agent shall,
          upon receipt of a Company Order, authenticate for original issue
          Notes in the aggregate principal amount at maturity specified in
          such Company Order; provided that the Trustee shall be entitled 
                              --------
          to receive an Officers' Certificate and an Opinion of Counsel of
          the Company if it so reasonably requests in connection with such
          authentication of Notes.  Such Company Order shall specify the
          amount of Notes to be authenticated, the date on which the issue
          of Notes is to be authenticated and in case of an issuance of
          Notes pursuant to Section 2.15, shall certify that such issuance
          is in compliance with Article Four.

                    The Trustee may appoint an authenticating agent to
          authenticate Notes.  An authenticating agent may authenticate
          Notes whenever the Trustee may do so.  Each reference in this
          Indenture to authentication by the Trustee includes
          authentication by such authenticating agent.  An authenticating
          agent has the same rights as an Agent to deal with the Company or
          an Affiliate of the Company.

                    The Notes shall be issuable only in registered form
          without coupons and only in denominations of $1,000 in principal
          amount at maturity and any integral multiple of $1,000 in excess
          thereof.

                    SECTION 2.04.  Registrar and Paying Agent.  The Company
                                   --------------------------
          shall maintain an office or agency where Notes may be presented
          for registration of transfer or for exchange (the "Registrar"), 
                                                             ---------
          an office or agency where Notes may be presented for payment (the
          "Paying Agent") and an office or agency where notices and demands 
           ------------
          to or upon the Company in respect of the Notes and this Indenture
          may be served, which shall be in the Borough of Manhattan, The
          City of New York.  The Company shall cause the Registrar to keep
          a register of the Notes and of their transfer and exchange (the
          "Note Register").  The Company may have one or more co-Registrars 
           -------------
          and one or more additional Paying Agents.

                    The Company shall enter into an appropriate agency
          agreement with any Agent not a party to this Indenture.  The
          agreement shall implement the provisions of this Indenture that
          relate to such Agent.  The Company shall give prompt written
          notice to the Trustee of the name and address of any such Agent
          and any change in the address of such Agent.  If the Company
          fails to maintain a Registrar, Paying Agent and/or agent for
          service of notices and demands, the Trustee shall act as such
          Registrar, Paying Agent and/or agent for service of notices and
          demands for so long as such failure shall continue.  The Company
          may remove any Agent upon written notice to such Agent and the
          Trustee; provided that no such removal shall become effective 
                   --------
          until (i) the acceptance of an appointment by a successor Agent
          to such Agent as evidenced by an appropriate agency agreement
          entered into by the Company and such successor Agent and
          delivered to the Trustee or (ii) notification to the Trustee that
          the Trustee shall serve as such Agent until the appointment of a
          successor Agent in accordance with clause (i) of this proviso. 
          The Company, any Subsidiary of the Company, or any Affiliate of
          any of them may act as Paying Agent, Registrar or co-Registrar,
          and/or agent for service of notice and demands; provided, 
                                                          --------
          however, that neither the Company, a Subsidiary of the Company 
          -------
          nor an Affiliate of any of them shall act as Paying Agent in
          connection with the defeasance of the Notes or the discharge of
          this Indenture under Article Eight.

                    The Company initially appoints the Trustee as
          Registrar, Paying Agent, authenticating agent and agent for
          service of notice and demands.  If, at any time, the Trustee is
          not the Registrar, the Registrar shall make available to the
          Trustee on or before each Interest Payment Date and at such other
          times as the Trustee may reasonably request, the names and
          addresses of the Holders as they appear in the Note Register.

                    SECTION 2.05.  Paying Agent to Hold Money in Trust.  
                                   -----------------------------------
          Not later than 10:00 a.m. New York City time on each due date of
          the principal, premium, if any, or interest on any Notes, the
          Company shall deposit with the Paying Agent money in immediately
          available funds sufficient to pay such principal, premium, if
          any, or interest so becoming due.  The Company shall require each
          Paying Agent, if any, other than the Trustee to agree in writing
          that such Paying Agent shall hold in trust for the benefit of the
          Holders or the Trustee all money held by the Paying Agent for the
          payment of principal of, premium, if any, or interest on the
          Notes (whether such money has been paid to it by the Company or
          any other obligor on the Notes), and that such Paying Agent shall
          promptly notify the Trustee of any default by the Company (or any
          other obligor on the Notes) in making any such payment.  The
          Company at any time may require a Paying Agent to pay all money
          held by it to the Trustee and account for any funds disbursed,
          and the Trustee may at any time during the continuance of any
          payment default, upon written request to a Paying Agent, require
          such Paying Agent to pay all money held by it to the Trustee and
          to account for any funds disbursed.  Upon doing so, the Paying
          Agent shall have no further liability for the money so paid over
          to the Trustee.  If the Company or any Subsidiary of the Company
          or any Affiliate of any of them acts as Paying Agent, it will, on
          or before each due date of any principal of, premium, if any, or
          interest on the Notes, segregate and hold in a separate trust
          fund for the benefit of the Holders a sum of money sufficient to
          pay such principal, premium, if any, or interest so becoming due
          until such sum of money shall be paid to such Holders or
          otherwise disposed of as provided in this Indenture, and will
          promptly notify the Trustee of its action or failure to act as
          required by this Section 2.05.

                    SECTION 2.06.  Transfer and Exchange.  The Notes are 
                                   ---------------------
          issuable only in registered form.  A Holder may transfer a Note
          by written application to the Registrar stating the name of the
          proposed transferee and otherwise complying with the terms of
          this Indenture.  No such transfer shall be effected until, and
          such transferee shall succeed to the rights of a Holder only upon
          registration of the transfer by the Registrar in the Note
          Register.  Prior to the registration of any transfer by a Holder
          as provided herein, the Company, the Trustee, and any agent of
          the Company shall treat the Person in whose name the Note is
          registered as the owner thereof for all purposes whether or not
          the Note shall be overdue, and neither the Company, the Trustee,
          nor any such agent shall be affected by notice to the contrary. 
          Furthermore, any Holder of a Global Note shall, by acceptance of
          such Global Note, agree that transfers of beneficial interests in
          such Global Note may be effected only through a book-entry system
          maintained by the Depository (or its agent), and that ownership
          of a beneficial interest in the Note shall be required to be
          reflected in a book entry.  When Notes are presented to the
          Registrar or a co-Registrar with a request to register the
          transfer or to exchange them for an equal principal amount at
          maturity of Notes of other authorized denominations (including on
          exchange of Notes for Exchange Notes), the Registrar shall
          register the transfer or make the exchange as requested if its
          requirements for such transactions are met; provided that no 
                                                      --------
          exchanges of Notes for Exchange Notes shall occur until a
          Registration Statement shall have been declared effective by the
          Commission and that any Notes that are exchanged for Exchange
          Notes shall be cancelled by the Trustee.  To permit registrations
          of transfers and exchanges in accordance with the terms,
          conditions and restrictions hereof, the Company shall execute and
          the Trustee shall authenticate Notes at the Registrar's request. 
          No service charge shall be made to any Holder for any
          registration of transfer or exchange or redemption of the Notes,
          but the Company may require payment of a sum sufficient to cover
          any transfer tax or similar governmental charge payable in
          connection therewith (other than any such transfer taxes or other
          similar governmental charge payable upon transfers, exchanges or
          redemptions pursuant to Section 2.11, 3.08, 4.11, 4.12 or 9.04).

                    The Registrar shall not be required (i) to issue,
          register the transfer of or exchange any Note during a period
          beginning at the opening of business 15 days before the day of
          the mailing of a notice of redemption of Notes selected for
          redemption under Section 3.03 or Section 3.08 and ending at the
          close of business on the day of such mailing, or (ii) to register
          the transfer of or exchange any Note so selected for redemption
          in whole or in part, except the unredeemed portion of any Note
          being redeemed in part.

                    SECTION 2.07.  Book-Entry Provisions for Global Notes. 
                                   --------------------------------------
          (a)  Each U.S. Global Note and Offshore Global Note initially
          shall (i) be registered in the name of the Depository for such
          Global Notes or the nominee of such Depository, (ii) be delivered
          to the Trustee as custodian for such Depository and (iii) bear
          legends as set forth in Section 2.02.

                    Members of, or participants in, the Depository ("Agent
                                                                     -----
          Members") shall have no rights under this Indenture with respect
          -------
          to any Global Note held on their behalf by the Depository, or the
          Trustee as its custodian, or under any Global Note, and the
          Depository may be treated by the Company, the Trustee and any
          agent of the Company or the Trustee as the absolute owner of such
          Global Note for all purposes whatsoever.  Notwithstanding the
          foregoing, nothing herein shall prevent the Company, the Trustee
          or any agent of the Company or the Trustee, from giving effect to
          any written certification, proxy or other authorization furnished
          by the Depository or impair, as between the Depository and its
          Agent Members, the operation of customary practices governing the
          exercise of the rights of a beneficial owner of any Note.

                    (b)    Transfers of a Global Note shall be limited to
          transfers of such Global Note in whole, but not in part, to the
          Depository, its successors or their respective nominees. 
          Interests of beneficial owners in a Global Note may be
          transferred in accordance with the applicable rules and
          procedures of the Depository and the provisions of Section 2.08. 
          In addition, U.S. Certificated Notes or Offshore Certificated
          Notes shall be transferred to all beneficial owners in exchange
          for their beneficial interests in a U.S. Global Note or an
          Offshore Global Note, respectively, if (i) the Depository
          notifies the Company that it is unwilling or unable to continue
          as Depository for the U.S. Global Notes or the Offshore Global
          Notes, as the case may be, and a successor depositary is not
          appointed by the Company within 90 days of such notice or (ii) an
          Event of Default has occurred and is continuing and the Registrar
          has received a request to the foregoing effect from the
          Depository.

                    (c)    Any beneficial interest in one of the Global
          Notes that is transferred to a Person who takes delivery in the
          form of an interest in the other Global Note will, upon transfer,
          cease to be an interest in such Global Note and become an
          interest in the other Global Note and, accordingly, will
          thereafter be subject to all transfer restrictions, if any, and
          other procedures applicable to beneficial interests in such other
          Global Note for as long as it remains such an interest.

                    (d)    In connection with any transfer pursuant to
          paragraph (b) of this Section of a portion of the beneficial
          interests in a U.S. Global Note or Offshore Global Note to
          beneficial owners who are required to hold U.S. Certificated
          Notes, the Registrar shall reflect on its books and records the
          date and a decrease in the principal amount at maturity of such
          U.S. Global Note or Offshore Global Note in an amount equal to
          the principal amount at maturity of the beneficial interest in
          such U.S. Global Note or Offshore Global Note to be transferred,
          and the Company shall execute, and the Trustee shall authenticate
          and deliver, one or more U.S. Certificated Notes or Offshore
          Certificated Notes, as the case may be, of like tenor and amount.

                    (e)    In connection with the transfer of all the U.S.
          Global Notes or Offshore Global Notes to beneficial owners
          pursuant to paragraph (b) of this Section, the U.S. Global Notes
          or Offshore Global Notes, as the case may be, shall be deemed to
          be surrendered to the Trustee for cancellation, and the Company
          shall execute, and the Trustee shall authenticate and deliver, to
          each beneficial owner identified by the Depository in exchange
          for its beneficial interest in the U.S. Global Notes or Offshore
          Global Notes, as the case may be, an equal aggregate principal
          amount at maturity of U.S. Certificated Notes or Offshore
          Certificated Notes, as the case may be, of authorized
          denominations.

                    (f)    Any U.S. Certificated Note delivered in exchange
          for an interest in a U.S. Global Note pursuant to paragraph (b),
          (d) or (e) of this Section shall, except as otherwise provided by
          paragraphs (f)(i)(x) and (d) of Section 2.08 hereof, bear the
          legend regarding transfer restrictions applicable to the U.S.
          Certificated Note set forth in Section 2.02.

                    (g)    Any Offshore Certificated Note delivered in
          exchange for an interest in an Offshore Global Note pursuant to
          paragraph (b), (d) or (e) of this Section shall, except as
          otherwise provided by paragraphs (f)(i)(x) and (d) of Section
          2.08 hereof, bear the legend regarding transfer restrictions
          applicable to the Offshore Certificated Note set forth in
          Section 2.02 hereof.

                    (h)    The registered holder of a Global Note may grant
          proxies and otherwise authorize any Person, including Agent
          Members and Persons that may hold interests through Agent
          Members, to take any action which a Holder is entitled to take
          under this Indenture or the Notes.

                    (i)    QIBs that are beneficial owners of interests in
          a Global Note may receive Certificated Notes (which shall bear
          the Private Placement Legend if required by Section 2.02) in
          accordance with the procedures of the Depository.  In connection
          with the execution, authentication and delivery of such
          Certificated Notes, the Registrar shall reflect on its books and
          records a decrease in the principal amount of the relevant Global
          Note equal to the principal amount of such Certificated Notes and
          the Company shall execute and the Trustee shall authenticate and
          deliver one or more Certificated  Notes having an equal aggregate
          principal amount.

                    SECTION 2.08.  Special Transfer Provisions.  Unless and
                                   ---------------------------
          until a Note is exchanged for an Exchange Note in connection with
          an effective Registration Statement pursuant to the Registration
          Rights Agreement, the following provisions shall apply:

                    (a)    Transfers to QIBs.  The following provisions 
                           -----------------
               shall apply with respect to the registration of any proposed
               transfer of a U.S. Certificated Note or an interest in a
               U.S. Global Note to a QIB (excluding Non-U.S. Persons):

                           (i)     If the Note to be transferred consists
                    of (x) U.S. Certificated Notes, the Registrar shall    
                    register the transfer if such transfer is being made by
                    a proposed transferor who has checked the box provided
                    for on the form of Note stating, or has otherwise
                    advised the Company and the Registrar in writing, that
                    the sale has been made in compliance with the
                    provisions of Rule 144A to a transferee who has signed
                    the certification provided for on the form of Note
                    stating, or has otherwise advised the Company and the
                    Registrar in writing, that it is purchasing the Note
                    for its own account or an account with respect to which
                    it exercises sole investment discretion and that it and
                    any such account is a QIB within the meaning of
                    Rule 144A, and is aware that the sale to it is being
                    made in reliance on Rule 144A and acknowledges that it
                    has received such information regarding the Company as
                    it has requested pursuant to Rule 144A or has
                    determined not to request such information and that it
                    is aware that the transferor is relying upon its
                    foregoing representations in order to claim the
                    exemption from registration provided by Rule 144A or
                    (y) an interest in a U.S. Global Note, the transfer of
                    such interest may be effected only through the book
                    entry system maintained by the Depository.

                           (ii)    If the proposed transferee is an Agent
                    Member, and the Note to be transferred consists of U.S.
                    Certificated Notes, upon receipt by the Registrar of
                    the documents referred to in clause (i) and
                    instructions given in accordance with the Depository's
                    and the Registrar's procedures, the Registrar shall
                    reflect on its books and records the date and an
                    increase in the principal amount at maturity of such
                    U.S. Global Note in an amount equal to the principal
                    amount at maturity of the U.S. Certificated Notes to be
                    transferred, and the Trustee shall cancel the
                    Certificated Note so transferred.

                    (b)    Transfers of Interests in Offshore Global Notes 
                           -----------------------------------------------
               or Offshore Certificated Notes to U.S. Persons.  The 
               ----------------------------------------------
               following provisions shall apply with respect to any
               transfer of interests in Offshore Global Notes or Offshore
               Certificated Notes to U.S. Persons:

                           (i)     prior to the removal of the Private
                    Placement Legend from Offshore Global Notes or Offshore
                    Certificated Notes pursuant to Section 2.02, the
                    Registrar shall refuse to register such transfer; and

                           (ii)    after such removal, the Registrar shall
                    register the transfer of any such Note without
                    requiring any additional certification.


                    (c)    Transfers to Non-U.S. Persons at Any Time.  The 
                           -----------------------------------------
               following provisions shall apply with respect to any
               transfer of a Note to a Non-U.S. Person:

                           (i)     The Registrar shall register any
                    proposed transfer to any Non-U.S. Person if the Note to
                    be transferred is a U.S. Certificated Note or an
                    interest in a U.S. Global Note only upon receipt of a
                    certificate substantially in the form of Exhibit C from
                    the proposed transferor.

                           (ii)    (A) If the proposed transferor is an
                    Agent Member holding a beneficial interest in a U.S.
                    Global Note, upon receipt by the Registrar of (x) the
                    documents required by paragraph (i) and
                    (y) instructions in accordance with the Depository's
                    and the Registrar's procedures, the Registrar shall
                    reflect on its books and records the date and a
                    decrease in the principal amount at maturity of such
                    U.S. Global Note in an amount equal to the principal
                    amount at maturity of the beneficial interest in the
                    U.S. Global Note to be transferred, and (B) if the
                    proposed transferee is an Agent Member, upon receipt by
                    the Registrar of instructions given in accordance with
                    the Depository's and the Registrar's procedures, the
                    Registrar shall reflect on its books and records the
                    date and an increase in the principal amount at
                    maturity of such Offshore Global Note in an amount
                    equal to the principal amount at maturity of the U.S.
                    Certificated Notes or the U.S. Global Notes, as the
                    case may be, to be transferred, and the Trustee shall
                    cancel the Certificated Note, if any, so transferred or
                    decrease the amount of the U.S. Global Notes.

                    (d)    Private Placement Legend.  Upon the registration
                           ------------------------
               of transfer, exchange or replacement of Notes not bearing
               the Private Placement Legend, the Registrar shall deliver
               Notes that do not bear the Private Placement Legend.  Upon
               the registration of transfer, exchange or replacement of
               Notes bearing the Private Placement Legend, the Registrar
               shall deliver only Notes that bear the Private Placement
               Legend unless either (i) the Private Placement Legend is no
               longer required by Section 2.02 or (ii) there is delivered
               to the Registrar an Opinion of Counsel reasonably
               satisfactory to the Company and the Trustee to the effect
               that neither such legend nor the related restrictions on
               transfer are required in order to maintain compliance with
               the provisions of the Securities Act.

                    (e)    General.  By its acceptance of any Note bearing 
                           -------
               the Private Placement Legend, each Holder of such a Note
               acknowledges the restrictions on transfer of such Note set
               forth in this Indenture and in the Private Placement Legend
               and agrees that it will transfer such Note only as provided
               in this Indenture.  The Registrar shall not register a
               transfer of any Note unless such transfer complies with the
               restrictions on transfer of such Note set forth in this
               Indenture.  In connection with any transfer of Notes to an
               Institutional Accredited Investor, each Holder agrees by its
               acceptance of the Notes to furnish the Registrar or the
               Company such certifications, legal opinions or other
               information as either of them may reasonably require to
               confirm that such transfer is being made pursuant to an
               exemption from, or a transaction not subject to, the
               registration requirements of the Securities Act; provided 
                                                                --------
               that the Registrar shall not be required to determine (but
               may rely on a determination made by the Company with respect
               to) the sufficiency of any such certifications, legal
               opinions or other information.

                    (f)    Transfers to Non-QIB Institutional Accredited 
                           ---------------------------------------------
               Investors.  The following provisions shall apply with 
               ---------
               respect to the registration of any proposed transfer of a
               Note to any Institutional Accredited Investor which is not a
               QIB (excluding Non-U.S. Persons):

                           (i)     The Registrar shall register the
                    transfer of any Note, whether or not such Note bears
                    the Private Placement Legend, if (x) the requested
                    transfer is after the time period referred to in Rule
                    144(k) under the Securities Act as in effect with
                    respect to such transfer or (y) the proposed transferee
                    has delivered to the Registrar (A) a certificate
                    substantially in the form of Exhibit D hereto and
                    (B) if the aggregate Accreted Value of Notes being
                    transferred is less than $250,000 at the time of such
                    transfer, an Opinion of Counsel acceptable to the
                    Company that such transfer is in compliance with the
                    Securities Act.

                           (ii)    If the proposed transferor is an Agent
                    Member holding a beneficial interest in a U.S. Global
                    Note, upon receipt by the Registrar and the Company of
                    (x) the documents, if any, required by paragraph (i)
                    and (y) instructions given in accordance with the
                    Depository's and the Registrar's procedures, the
                    Registrar shall reflect on its books and records the
                    date and a decrease in the principal amount at maturity
                    of such U.S. Global Note in an amount equal to the
                    principal amount at maturity of the beneficial interest
                    in the U.S. Global Note to be transferred, and the
                    Company shall execute, and the Trustee shall
                    authenticate and deliver, one or more U.S. Certificated
                    Notes of like tenor and amount.

                    The Registrar shall retain copies of all letters,
          notices and other written communications received pursuant to
          Section 2.07 or this Section 2.08.  The Company shall have the
          right to inspect and make copies of all such letters, notices or
          other written communications at any reasonable time upon the
          giving of reasonable written notice to the Registrar.

                    SECTION 2.09.  Replacement Notes.  If a mutilated Note
                                   -----------------
          is surrendered to the Trustee or if the Holder claims that the
          Note has been lost, destroyed or wrongfully taken, the Company
          shall issue and the Trustee shall authenticate a replacement Note
          of like tenor and principal amount and bearing a number not
          contemporaneously outstanding; provided that the requirements of
                                         --------
          the second paragraph of Section 2.10 are met.  If required by the
          Trustee or the Company, an indemnity bond must be furnished that
          is sufficient in the judgment of both the Trustee and the Company
          to protect the Company, the Trustee or any Agent from any loss
          that any of them may suffer if a Note is replaced.  The Company
          may charge such Holder for its expenses and the expenses of the
          Trustee in replacing a Note.  In case any such mutilated, lost,
          destroyed or wrongfully taken Note has become or is about to
          become due and payable, the Company in its discretion may pay
          such Note instead of issuing a new Note in replacement thereof.

                    Every replacement Note is an additional obligation of
          the Company and shall be entitled to the benefits of this
          Indenture.

                    SECTION 2.10.  Outstanding Notes.  Notes outstanding at
                                   -----------------
          any time are all Notes that have been authenticated by the
          Trustee except for those cancelled by it, those delivered to it
          for cancellation and those described in this Section 2.10 as not
          outstanding.

                    If a Note is replaced pursuant to Section 2.09, it
          ceases to be outstanding unless and until the Trustee and the
          Company receive proof reasonably satisfactory to them that the
          replaced Note is held by a bona fide purchaser.

                    If the Paying Agent (other than the Company or an
          Affiliate of the Company) holds on the maturity date or a
          redemption date money sufficient to pay all principal, premium,
          if any, and interest payable on that date with respect to the
          Notes (or portions thereof) to be redeemed or payable on that
          date, then on and after that date such Notes cease to be
          outstanding and interest on them shall cease to accrue or the
          principal of such Notes shall cease to accrete, the case may be.

                    A Note does not cease to be outstanding because the
          Company or one of its Affiliates holds such Note; provided, 
                                                            --------
          however, that, in determining whether the Holders of the 
          -------
          requisite principal amount at maturity of the outstanding Notes
          have given any request, demand, authorization, direction, notice,
          consent or waiver hereunder, Notes owned by the Company or any
          other obligor upon the Notes or any Affiliate of the Company or
          of such other obligor shall be disregarded and deemed not to be
          outstanding, except that, in determining whether the Trustee
          shall be protected in relying upon any such request, demand,
          authorization, direction, notice, consent or waiver, only Notes
          which the Trustee knows to be so owned shall be so disregarded. 
          Notes so owned which have been pledged in good faith may be
          regarded as outstanding if the pledgee establishes to the
          satisfaction of the Trustee the pledgee's right so to act with
          respect to such Notes and that the pledgee is not the Company or
          any other obligor upon the Notes or any Affiliate of the Company
          or of such other obligor.

                    SECTION 2.11.  Temporary Notes.  Until definitive Notes
                                   ---------------
          are ready for delivery, the Company may prepare and the Trustee
          shall authenticate temporary Notes.  Temporary Notes shall be
          substantially in the form of definitive Notes but may have
          insertions, substitutions, omissions and other variations
          determined to be appropriate by the Officers executing the
          temporary Notes, as evidenced by their execution of such
          temporary Notes.  If temporary Notes are issued, the Company will
          cause definitive Notes to be prepared without unreasonable delay. 
          After the preparation of definitive Notes, the temporary Notes
          shall be exchangeable for definitive Notes upon surrender of the
          temporary Notes at the office or agency of the Company designated
          for such purpose pursuant to Section 4.02, without charge to the
          Holder.  Upon surrender for cancellation of any one or more
          temporary Notes the Company shall execute and the Trustee shall
          authenticate and deliver in exchange therefor a like principal
          amount at maturity of definitive Notes of authorized
          denominations.  Until so exchanged, the temporary Notes shall be
          entitled to the same benefits under this Indenture as definitive
          Notes.

                    SECTION 2.12.  Cancellation.  The Company at any time 
                                   ------------
          may deliver to the Trustee for cancellation any Notes previously
          authenticated and delivered hereunder which the Company may have
          acquired in any manner whatsoever, and may deliver to the Trustee
          for cancellation any Notes previously authenticated hereunder
          which the Company has not issued and sold.  The Registrar and the
          Paying Agent shall forward to the Trustee any Notes surrendered
          to them for registration of transfer, exchange, purchase or
          payment.  The Trustee shall cancel all Notes surrendered for
          registration of transfer, exchange, purchase, payment or
          cancellation and shall dispose of them in accordance with its
          normal procedure.  The Company shall not issue new Notes to
          replace Notes it has paid in full or delivered to the Trustee for
          cancellation.

                    SECTION 2.13.  CUSIP Numbers.  The Company in issuing 
                                   -------------
          the Notes may use "CUSIP" and "CINS" numbers (if then generally
          in use), and the Trustee shall use CUSIP numbers or CINS numbers,
          as the case may be, in notices of redemption or exchange as a
          convenience to Holders; provided that any such notice shall state
                                  --------
          that no representation is made as to the correctness of such
          numbers either as printed on the Notes or as contained in any
          notice of redemption or exchange and that reliance may be placed
          only on the other identification numbers printed on the Notes.

                    SECTION 2.14.  Defaulted Interest.  If the Company 
                                   ------------------
          defaults in a payment of interest on the Notes, it shall pay, or
          shall deposit with the Paying Agent money in immediately
          available funds sufficient to pay, the defaulted interest, plus
          (to the extent lawful)  interest on the defaulted interest, to
          the Persons who are Holders on a subsequent special record date. 
          A special record date, as used in this Section 2.14 with respect
          to the payment of any defaulted interest, shall mean the 15th day
          next preceding the date fixed by the Company for the payment of
          defaulted interest, whether or not such day is a Business Day. 
          At least 15 days before the subsequent special record date, the
          Company shall mail to each Holder and to the Trustee a notice
          that states the subsequent special record date, the payment date
          and the amount of defaulted interest to be paid.

                    SECTION 2.15.  Issuance of Additional Notes.  The 
                                   ----------------------------
          Company may, subject to Article Four of this Indenture, issue
          additional Notes under this Indenture.  The Notes issued on the
          Closing Date and any additional Notes subsequently issued shall
          be treated as a single class for all purposes under this
          Indenture.


                                    ARTICLE THREE
                                      REDEMPTION

                    SECTION 3.01.  Right of Redemption.  (a)  The Notes may
                                   -------------------
          be redeemable, at the Company's option, in whole or in part, at
          any time or from time to time, on or after February 15, 2003 and
          prior to maturity, upon not less than 30 nor more than 60 days'
          prior notice mailed by first class mail to each Holder's last
          address as it appears in the Note Register, at the Redemption
          Prices (expressed in percentages of principal amount at
          maturity), plus accrued and unpaid interest, if any, to the
          Redemption Date (subject to the right of Holders of record on the
          relevant Regular Record Date that is on or prior to the
          Redemption Date to receive interest due on an Interest Payment
          Date), if redeemed during the 12-month period commencing February
          15, of the years set forth below:

                          YEAR                    REDEMPTION PRICE
                          ----                    ----------------
                          2003                      105.0000%
                          2004                      103.3333 
                          2005                      101.6667
                          2006 and thereafter       100.0000 

                    (b)  In addition, at any time or from time to time, on
          or prior to February 15, 2001, the Company may, at its option,
          redeem Notes having an aggregate principal amount at maturity of
          up to 35% of the aggregate principal amount at maturity of the
          Notes with the proceeds of one or more public or private Equity
          Offerings, at a Redemption Price equal to 110.0% of the Accreted
          Value thereof on the Redemption Date; provided that at least 65%
                                                --------
          of the aggregate principal amount of Notes initially issued
          remains outstanding after each such redemption.

                    SECTION 3.02.  Notices to Trustee.  If the Company 
                                   ------------------
          elects to redeem Notes pursuant to Section 3.01, it shall notify
          the Trustee in writing of the Redemption Date and the principal
          amount at maturity of Notes to be redeemed.

                    The Company shall give each notice provided for in this
          Section 3.02 in an Officers' Certificate at least 60 days before
          the Redemption Date (unless a shorter period shall be
          satisfactory to the Trustee).

                    SECTION 3.03.  Selection of Notes to Be Redeemed.  If 
                                   ---------------------------------
          less than all of the Notes are to be redeemed at any time, the
          Trustee shall select the Notes to be redeemed in compliance with
          the requirements of the principal national securities exchange,
          if any, on which the Notes are listed or if the Notes are not
          listed on a national securities exchange, on a pro rata basis or
          by lot or by such other method as the Trustee in its sole
          discretion shall deem to be fair and appropriate; provided that
          no Notes of $1,000 in principal amount at maturity or less shall
          be redeemed in part.

                    The Trustee shall make the selection from the Notes
          outstanding and not previously called for redemption.  Notes in
          denominations of $1,000 in principal amount at maturity may only
          be redeemed in whole.  The Trustee may select for redemption
          portions (equal to $1,000 in principal amount at maturity or any
          integral multiple thereof) of Notes that have denominations
          larger than $1,000 in principal amount at maturity.  Provisions
          of this Indenture that apply to Notes called for redemption also
          apply to portions of Notes called for redemption.  The Trustee
          shall notify the Company and the Registrar promptly in writing of
          the Notes or portions of Notes to be called for redemption.

                    SECTION 3.04.  Notice of Redemption.  With respect to 
                                   --------------------
          any redemption of Notes pursuant to Section 3.01, at least 30
          days but not more than 60 days before a Redemption Date, the
          Company shall mail a notice of redemption by first class mail to
          each Holder whose Notes are to be redeemed.

                    The notice shall identify the Notes to be redeemed and
          shall state:

                    (i)   the Redemption Date;

                    (ii)  the Redemption Price;

                    (iii) the name and address of the Paying Agent;

                    (iv)  that Notes called for redemption must be
               surrendered to the Paying Agent in order to collect the
               Redemption Price;

                    (v)  that, unless the Company defaults in making the
               redemption payment, interest on Notes (or portions thereof)
               called for redemption ceases to accrue or Notes called for
               redemption cease to accrete in value, as the case may be, on
               and after the Redemption Date and the only remaining right
               of the Holders is to receive payment of the Redemption Price
               plus accrued interest to the Redemption Date upon surrender
               of the Notes to the Paying Agent;

                    (vi)  that, if any Note is being redeemed in part, the
               portion of the principal amount at maturity (equal to $1,000
               in principal amount at maturity or any integral multiple
               thereof) of such Note to be redeemed and that, on and after
               the Redemption Date, upon surrender of such Note, a new Note
               or Notes in principal amount at maturity equal to the
               unredeemed portion thereof will be reissued; and

                    (vii)  that, if any Note contains a CUSIP number as
               provided in Section 2.13, no representation is being made as
               to the correctness of the CUSIP number either as printed on
               the Notes or as contained in the notice of redemption.

                    At the Company's request (which request may be revoked
          by the Company at any time prior to the time at which the Trustee
          shall have given such notice to the Holders), made in writing to
          the Trustee at least 60 days (or such shorter period as shall be
          satisfactory to the Trustee) before a Redemption Date, the
          Trustee shall give the notice of redemption in the name and at
          the expense of the Company.  If, however, the Company gives such
          notice to the Holders, the Company shall concurrently deliver to
          the Trustee an Officers' Certificate stating that such notice has
          been given.

                    SECTION 3.05.  Effect of Notice of Redemption.  Once 
                                   ------------------------------
          notice of redemption is mailed, Notes called for redemption
          become due and payable on the Redemption Date and at the
          Redemption Price.  Upon surrender of any Notes to the Paying
          Agent, such Notes shall be paid at the Redemption Price, plus
          accrued interest, if any, to the Redemption Date.

                    Notice of redemption shall be deemed to be given when
          mailed, whether or not the Holder receives the notice.  In any
          event, failure to give such notice, or any defect therein, shall
          not affect the validity of the proceedings for the redemption of
          Notes held by Holders to whom such notice was properly given.

                    SECTION 3.06.  Deposit of Redemption Price.  On or 
                                   ---------------------------
          prior to any Redemption Date, the Company shall deposit with the
          Paying Agent (or, if the Company is acting as its own Paying
          Agent, shall segregate and hold in trust as provided in Section
          2.05) money sufficient to pay the Redemption Price of and accrued
          interest on all Notes to be redeemed on that date other than
          Notes or portions thereof called for redemption on that date that
          have been delivered by the Company to the Trustee for
          cancellation.

                    SECTION 3.07.  Payment of Notes Called for Redemption. 
                                   --------------------------------------
          If notice of redemption has been given in the manner provided
          above, the Notes or portion of Notes specified in such notice to
          be redeemed shall become due and payable on the Redemption Date
          at the Redemption Price stated therein, together with accrued
          interest to such Redemption Date, and on and after such date
          (unless the Company shall default in the payment of such Notes at
          the Redemption Price and accrued interest to the Redemption Date,
          in which case the principal, until paid, shall bear interest from
          the Redemption Date at the rate prescribed in the Notes), such
          Notes shall cease to accrue interest or accrete in value, as the
          case may be.  Upon surrender of any Note for redemption in
          accordance with a notice of redemption, such Note shall be paid
          and redeemed by the Company at the Redemption Price, together
          with accrued interest, if any, to the Redemption Date; provided 
                                                                 --------
          that installments of interest whose Stated Maturity is on or
          prior to the Redemption Date shall be payable to the Holders
          registered as such at the close of business on the relevant
          Regular Record Date.

                    SECTION 3.08.  Notes Redeemed in Part.  Upon surrender
                                   ----------------------  
          of any Note that is redeemed in part, the Company shall execute
          and the Trustee shall authenticate and deliver to the Holder a
          new Note equal in principal amount at maturity to the unredeemed
          portion of such surrendered Note.


                                     ARTICLE FOUR
                                      COVENANTS

                    SECTION 4.01.  Payment of Notes.  The Company shall pay
                                   ----------------
          the principal of, premium, if any, and interest on the Notes on
          the dates and in the manner provided in the Notes and this
          Indenture.  An installment of principal, premium, if any, or
          interest shall be considered paid on the date due if the Trustee
          or Paying Agent (other than the Company, a Subsidiary of the
          Company, or any Affiliate of any of them) holds on that date
          money designated for and sufficient to pay the installment.  If
          the Company or any Subsidiary of the Company or any Affiliate of
          any of them, acts as Paying Agent, an installment of principal,
          premium, if any, or interest shall be considered paid on the due
          date if the entity acting as Paying Agent complies with the last
          sentence of Section 2.05.  As provided in Section 6.09, upon any
          bankruptcy or reorganization procedure relative to the Company,
          the Trustee shall serve as the Paying Agent and conversion agent,
          if any, for the Notes.

                    The Company shall pay interest on overdue principal,
          premium, if any, and interest on overdue installments of
          interest, to the extent lawful, at the rate per annum specified
          in the Notes.

                    SECTION 4.02.  Maintenance of Office or Agency.  The 
                                   -------------------------------
          Company will maintain in the Borough of Manhattan, the City of
          New York, an office or agency where Notes may be surrendered for
          registration of transfer or exchange or for presentation for
          payment and where notices and demands to or upon the Company in
          respect of the Notes and this Indenture may be served.  The
          Company will give prompt written notice to the Trustee of the
          location, and any change in the location, of such office or
          agency.  If at any time the Company shall fail to maintain any
          such required office or agency or shall fail to furnish the
          Trustee with the address thereof, such presentations, surrenders,
          notices and demands may be made or served at the address of the
          Trustee set forth in Section 10.02 hereof.

                    The Company may also from time to time designate one or
          more other offices or agencies where the Notes may be presented
          or surrendered for any or all such purposes and may from time to
          time rescind such designations; provided that no such designation
                                          --------
          or rescission shall in any manner relieve the Company of its
          obligation to maintain an office or agency in the Borough of
          Manhattan, the City of New York for such purposes.  The Company
          will give prompt written notice to the Trustee of any such
          designation or rescission and of any change in the location of
          any such other office or agency.

                    The Company hereby initially designates the Corporate
          Trust Office of the Trustee, located in the Borough of Manhattan,
          the City of New York, as such office of the Company in accordance
          with Section 2.04.

                    SECTION 4.03.  Limitation on Indebtedness.  (a)  The 
                                   --------------------------
          Company will not, and will not permit any of its Restricted
          Subsidiaries to, Incur any Indebtedness (other than the Notes and
          Indebtedness existing on the Closing Date); provided that the 
                                                      --------
          Company may Incur Indebtedness if, after giving effect to the
          Incurrence of such Indebtedness and the receipt and application
          of the proceeds therefrom, the Consolidated Leverage Ratio would
          be greater than zero and less than 6:1.

                    Notwithstanding the foregoing, the Company and any
          Restricted Subsidiary (except as specified below) may Incur each
          and all of the following:

                    (i)    Indebtedness of the Company or its Restricted
               Subsidiaries outstanding at any time in an aggregate
               principal amount not to exceed (A) $200 million of
               unsubordinated Indebtedness (including any Indebtedness
               under one or more revolving credit or working capital
               facilities) and (B) $200 million of subordinated
               Indebtedness (and any Guarantees thereof by the Company or
               its Restricted Subsidiaries), less any amount of such
               Indebtedness permanently repaid as provided under Section
               4.11 hereof;

                    (ii)   the Incurrence by the Company of Indebtedness
               represented by the Notes;

                    (iii)  Indebtedness in existence on the Closing Date;

                    (iv)   Indebtedness of the Company to a Restricted
               Subsidiary and Indebtedness of a Restricted Subsidiary to
               the Company or another Restricted Subsidiary; provided that
                                                             --------
               such Indebtedness is made pursuant to an intercompany note
               (which, in the case of Indebtedness owed to the Company,
               shall be unsubordinated) and any event which results in any
               such Restricted Subsidiary ceasing to be a Restricted
               Subsidiary or any subsequent transfer of such Indebtedness
               (other than to the Company or another Restricted Subsidiary)
               shall be deemed, in each case, to constitute an Incurrence
               of such Indebtedness not permitted by this clause (iv);

                    (v)    Indebtedness issued in exchange for, or the net
               proceeds of which are used to refinance or refund, then
               outstanding Indebtedness (other than Indebtedness Incurred
               under clause (i), (iv), (vi) or (viii) of this paragraph)
               and any refinancings thereof in an amount not to exceed the
               amount so refinanced or refunded (plus premiums, accrued
               interest, fees and expenses); provided that Indebtedness the
                                             --------
               proceeds of which are used to refinance or refund
               Indebtedness that is subordinated in right of payment to the
               Notes shall only be permitted under this clause (v) if (A)
               such new Indebtedness, by its terms or by the terms of any
               agreement or instrument pursuant to which such new
               Indebtedness is issued or remains outstanding, is expressly
               made subordinate in right of payment to the Notes at least
               to the extent that the Indebtedness to be refinanced is
               subordinated to the Notes and (B) such new Indebtedness,
               determined as of the date of Incurrence of such new
               Indebtedness, does not mature prior to the Stated Maturity
               of the Indebtedness to be refinanced or refunded, and the
               Average Life of such new Indebtedness is at least equal to
               the remaining Average Life of the Indebtedness to be
               refinanced or refunded; and provided further that in no 
                                           -------- -------
               event may Indebtedness of the Company be refinanced by means
               of any Indebtedness of any Restricted Subsidiary pursuant to
               this clause (v);

                    (vi)   Indebtedness (A) in respect of performance,
               surety or appeal bonds provided in the ordinary course of
               business, (B) under Currency Agreements and Interest Rate
               Agreements; provided that such agreements (a) are designed
                           --------                                   
               solely to protect the Company or its Restricted Subsidiaries
               against fluctuations in foreign currency exchange rates or
               interest rates and (b) do not increase the Indebtedness of
               the obligor outstanding at any time (except to the extent
               Incurred under another clause hereof) other than as a result
               of fluctuations in foreign currency exchange rates or
               interest rates or by reason of fees, indemnities and
               compensation payable thereunder; and (C) arising from
               agreements providing for indemnification, adjustment of
               purchase price or similar obligations, or from Guarantees or
               letters of credit, surety bonds or performance bonds
               securing any obligations of the Company or any of its
               Restricted Subsidiaries pursuant to such agreements, in each
               case Incurred in connection with the disposition of any
               business, assets or Restricted Subsidiary (other than
               Guarantees of Indebtedness Incurred by any Person acquiring
               all or any portion of such business, assets or Restricted
               Subsidiary for the purpose of financing such acquisition),
               in a principal amount not to exceed the gross proceeds
               actually received by the Company or any Restricted
               Subsidiary in connection with such disposition;

                    (vii)  Indebtedness of the Company, to the extent the
               net proceeds thereof are promptly (A) used to purchase Notes
               tendered in an Offer to Purchase made as a result of a
               Change in Control or (B) deposited to defease the Notes as
               described below under Article Eight hereof;

                    (viii) Guarantees of the Notes and Guarantees of
               Indebtedness of the Company by any Restricted Subsidiary
               provided the Guarantee of such Indebtedness is permitted by
               and made in accordance with Section 4.07 hereof and any
               Guarantee by the Company of Indebtedness or other
               obligations of any of its Restricted Subsidiaries so long as
               the incurrence of such Indebtedness Incurred by such
               Restricted Subsidiary is permitted under the terms of this
               Section 4.03;

                    (ix)   Indebtedness Incurred to finance the cost
               (including, without limitation, the cost of design,
               development, acquisition, construction, installation,
               improvement, transportation or integration) to acquire
               equipment, inventory, assets, services and related costs in
               connection with the Internet Service Business or the
               Telecommunications Business (including, without limitation,
               acquisitions by way of acquisitions of real property,
               leasehold improvements, licenses, rights-of-use, Capitalized
               Leases, installment sales and acquisitions of the Capital
               Stock of a Person that becomes a Restricted Subsidiary to
               the extent of the fair market value of the equipment,
               inventory or network assets so acquired) by the Company or a
               Restricted Subsidiary after the Closing Date;

                    (x)    Indebtedness of the Company not to exceed, at
               any one time outstanding, the sum (without duplication) of
               (A) two times the Net Cash Proceeds received by the Company
               from the sale of ICG Common Stock contributed by ICG to the
               Company after the Closing Date to a Person that is not a
               Subsidiary of the Company (1.6 times the closing price, last
               sale price or similar price of such ICG Common Stock at the
               time received by the Company to the extent such ICG Common
               Stock has not been sold) plus (B) two times cash or cash
               equivalents contributed by ICG or its Subsidiaries (other
               than the Company and its Subsidiaries) to the Company after
               the Closing Date plus (C) 1.6 times the fair market value of
               other assets (including, without limitation, Capital Stock)
               acquired by the Company or its Restricted Subsidiaries to
               the extent that the consideration therefor consists of ICG
               Common Stock plus (D) 1.6 times the fair market value of
               other assets contributed by ICG or its Subsidiaries (other
               than the Company and its Subsidiaries) to the Company after
               the Closing Date plus (E) two times the Net Cash Proceeds
               received by the Company after the Closing Date from the
               issuance and sale of its Capital Stock (other than
               Disqualified Stock) to a Person that is not a Subsidiary of
               the Company plus (F) 1.6 times the fair market value of
               property (other than cash and cash equivalents) received by
               the Company after the Closing Date from the sale of its
               Capital Stock (other than Disqualified Stock) to a Person
               that is not a Subsidiary of the Company, in each case, to
               the extent such Net Cash Proceeds, ICG Common Stock, cash or
               cash equivalents or such other assets or property have not
               been used pursuant to clause (C)(2) of the first paragraph
               or clause (iii) or (iv), as the case may be, of the second
               paragraph of Section 4.04; provided that such Indebtedness 
                                          --------
               does not mature prior to the Stated Maturity of the Notes
               and has a then current Average Life at least as long as the
               Notes;

                    (xi)   Indebtedness Incurred by the Company or any of
               its Restricted Subsidiaries constituting reimbursement
               obligations with respect to letters of credit in the
               ordinary course of business, including, without limitation,
               letters of credit in respect of workers' compensation claims
               or self insurance, or other Indebtedness with respect to
               reimbursement type obligations regarding workers'
               compensation claims; provided, however, that upon the 
                                    --------  -------
               drawing of such letters of credit or the Incurrence of such
               Indebtedness, such obligations are reimbursed within 30 days
               following such drawing or Incurrence;

                    (xii)  Acquired Indebtedness or Indebtedness of Persons
               that are acquired by the Company or any of its Restricted
               Subsidiaries or merged into a Restricted Subsidiary in
               accordance with the terms of this Indenture; provided that 
                                                            --------
               such Indebtedness is not incurred in contemplation of such
               acquisition or merger; and

                    (xiii) Strategic Subordinated Indebtedness.

                    (b)    Notwithstanding any other provision of this
          Section 4.03, the maximum amount of Indebtedness that the Company
          or a Restricted Subsidiary may Incur pursuant to this Section
          4.03 shall not be deemed to be exceeded, with respect to any
          outstanding Indebtedness due solely to the result of fluctuations
          in the exchange rates of currencies. Accretion on an instrument
          issued at a discount will not be deemed to constitute an
          Incurrence of Indebtedness.

                    (c)    For purposes of determining any particular
          amount of Indebtedness under this Section 4.03, (1) Guarantees,
          Liens or obligations with respect to letters of credit supporting
          Indebtedness otherwise included in the determination of such
          particular amount shall not be included and (2) any Liens granted
          pursuant to the equal and ratable provisions referred to in
          Section 4.09 hereof shall not be treated as Indebtedness. For
          purposes of determining compliance with this Section 4.03, in the
          event that an item of Indebtedness meets the criteria of more
          than one of the types of Indebtedness described in clauses (i)
          through (xiii) of Section 4.03(a), the Company, in its sole
          discretion, shall classify such item of Indebtedness and only be
          required to include the amount and type of such Indebtedness in
          one of such clauses.

                    SECTION 4.04.  Limitation on Restricted Payments.   The
                                   ---------------------------------
          Company will not, and will not permit any Restricted Subsidiary
          to, directly or indirectly, (i) declare or pay any dividend or
          make any distribution on or with respect to its Capital Stock
          (other than (x) dividends or distributions payable solely in
          shares of its Capital Stock (other than Disqualified Stock) or in
          options, warrants or other rights to acquire shares of such
          Capital Stock and (y) pro rata dividends or distributions on
          Common Stock of Restricted Subsidiaries held by minority
          stockholders) held by Persons other than the Company or any of
          its Restricted Subsidiaries, (ii) purchase, redeem, retire or
          otherwise acquire for value any shares of Capital Stock of (A)
          the Company or an Unrestricted Subsidiary (including options,
          warrants or other rights to acquire such shares of Capital Stock)
          held by any Person or (B) a Restricted Subsidiary (including
          options, warrants or other rights to acquire such shares of
          Capital Stock) held by any Affiliate of the Company (other than a
          Wholly Owned Restricted Subsidiary), (iii) make any voluntary or
          optional principal payment, or voluntary or optional redemption,
          repurchase, defeasance, or other acquisition or retirement for
          value, of Indebtedness of the Company that is subordinated in
          right of payment to the Notes (other than the purchase,
          redemption, repurchase or other acquisition of such subordinated
          Indebtedness purchased in anticipation of satisfying a sinking
          fund obligation, principal installment or final maturity, in each
          case due within six months of the date of acquisition) or
          (iv) make any Investment, other than a Permitted Investment, in
          any Person (such payments or any other actions described in
          clauses (i) through (iv) above being collectively "Restricted 
                                                             ----------
          Payments") if, at the time of, and after giving effect to, the 
          --------
          proposed Restricted Payment:  (A) a Default or Event of Default
          shall have occurred and be continuing, (B) except with respect to
          making any Investments, the Company could not Incur at least
          $1.00 of Indebtedness under the first paragraph of Section 4.03
          or (C) the aggregate amount of all Restricted Payments (the
          amount, if other than in cash, to be determined in good faith by
          the Board of Directors, whose determination shall be conclusive
          and evidenced by a Board Resolution) made after the Closing Date
          shall exceed the sum of (1) 50% of the aggregate amount of the
          Adjusted Consolidated Net Income (or, if the Adjusted
          Consolidated Net Income is a loss, minus 100% of the amount of
          such loss) (determined by excluding income resulting from
          transfers of assets by the Company or a Restricted Subsidiary to
          an Unrestricted Subsidiary) accrued on a cumulative basis during
          the period (taken as one accounting period) beginning on the
          first day of the fiscal quarter immediately following the Closing
          Date and ending on the last day of the last fiscal quarter
          preceding the Transaction Date for which reports have been filed
          with the Commission or provided to the Trustee pursuant to
          Section 4.18 hereof plus (2) 100% of (I) the aggregate Net Cash
          Proceeds or fair market value of any Capital Stock and the amount
          of cash from any capital contributions to the Company after the
          Closing Date from Persons other than Subsidiaries of the Company
          (including contributions of ICG Common Stock, cash and cash
          equivalents and other assets to the Company by ICG) plus (II) the
          aggregate Net Cash Proceeds received by the Company after the
          Closing Date from an issuance and sale of its Capital Stock
          (other than Disqualified Stock) to a Person who is not a
          Subsidiary of the Company, including, without limitation, an
          issuance or sale permitted by this Indenture for cash subsequent
          to the Closing Date upon the conversion of such Indebtedness into
          Capital Stock (other than Disqualified Stock) of the Company, or
          from the issuance to a Person who is not a Subsidiary of the
          Company of any options, warrants or other rights to acquire
          Capital Stock of the Company (in each case, exclusive of any
          Disqualified Stock or any options, warrants or other rights that
          are redeemable at the option of the holder, or are required to be
          redeemed, prior to the Stated Maturity of the Notes), to the
          extent such Net Cash Proceeds, Capital Stock, marketable
          securities or amount have not been previously applied pursuant to
          clauses (iii) or (iv), as the case may be, of the second
          paragraph of this Section 4.04 or used to support the Incurrence
          of Indebtedness pursuant to clause (x) of the second paragraph
          under Section 4.03 plus (3) amounts received from Investments
          (other than Permitted Investments) in any Person resulting from
          payments of interest on Indebtedness, dividends, repayments of
          loans or advances, or other transfers of assets, in each case to
          the Company or any Restricted Subsidiary or from the Net Cash
          Proceeds from the sale of any such Investment (except, in each
          case, to the extent any such payment or proceeds are included in
          the calculation of Adjusted Consolidated Net Income), or from
          redesignations of Unrestricted Subsidiaries as Restricted
          Subsidiaries (valued in each case as provided in the definition
          of "Investments"), not to exceed, in each case, the amount of
          Investments previously made by the Company or any Restricted
          Subsidiary in such Person or Unrestricted Subsidiary.

                    The foregoing provision shall not be violated by reason
          of:

                    (i)    the payment of any dividend within 60 days after
               the date of declaration thereof if, at said date of
               declaration, such payment would comply with the foregoing
               paragraph;

                    (ii)   the redemption, repurchase, defeasance or other
               acquisition or retirement for value of Indebtedness that is
               subordinated in right of payment to the Notes including
               premium, if any, and accrued and unpaid interest, with the
               proceeds of, or in exchange for, Indebtedness Incurred under
               clause (v) of the second paragraph of part (a) of Section
               4.03;

                    (iii)  the making of any principal payment or the
               repurchase, redemption, retirement, defeasance or other
               acquisition for value of Indebtedness of the Company which
               is subordinated in right of payment to the Notes (A) with
               cash or cash equivalents contributed by ICG to the Company
               after the Closing Date or (B) with, or out of the Net Cash
               Proceeds of, ICG Common Stock or other assets (other than
               cash or cash equivalents) contributed by ICG to the Company
               after the Closing Date, or (C) in exchange for, or out of,
               the Net Cash Proceeds of a substantially concurrent offering
               of shares of Capital Stock (other than Disqualified Stock)
               of the Company (or options, warrants or other rights to
               acquire such Capital Stock), to the extent such Net Cash
               Proceeds, cash or cash equivalents, ICG Common Stock,
               Capital Stock or such other assets have not been used
               pursuant to clause (C)(2) of the first paragraph or clause
               (iv) of the second paragraph, as the case may be, of this
               Section 4.04 or used to support the Incurrence of
               Indebtedness pursuant to clause (x) of the second paragraph
               under Section 4.03;

                    (iv)   the repurchase, redemption or other acquisition
               of Capital Stock of the Company or an Unrestricted
               Subsidiary (or options, warrants or other rights to acquire
               such Capital Stock) in exchange for, or out of the proceeds
               of a substantially concurrent offering of, shares of Capital
               Stock (other than Disqualified Stock) of the Company (or
               options, warrants or other rights to acquire such Capital
               Stock); or

                    (v)    other Restricted Payments in an aggregate amount
               not to exceed $10 million;

          provided that, except in the case of clauses (i), (ii), (iii) and
          --------
          (iv), no Default or Event of Default shall have occurred and be
          continuing or occur as a consequence of the actions or payments
          set forth therein.

                    Each Restricted Payment permitted pursuant to the
          preceding paragraph (other than the Restricted Payment referred
          to in clause (ii) thereof shall be included in calculating
          whether the conditions of clause (C) of clause (iv) of the first
          paragraph of this Section 4.04 have been met with respect to any
          subsequent Restricted Payments.

                    Any Restricted Payments made other than in cash shall
          be valued at fair market value. The amount of any Investment
          "outstanding" at any time shall be deemed to be equal to the
          amount of such Investment on the date made, less the return of
          capital to the Company and its Restricted Subsidiaries with
          respect to such Investment by distribution, sale or otherwise (up
          to the amount of such Investment on the date made).

                    SECTION 4.05.  Limitation on Dividend and Other Payment
                                   ----------------------------------------
          Restrictions Affecting Restricted Subsidiaries.  The Company will
          ----------------------------------------------
          not, and will not permit any Restricted Subsidiary to, create or
          otherwise cause or suffer to exist or become effective any
          consensual encumbrance or restriction of any kind on the ability
          of any Restricted Subsidiary to (i) pay dividends or make any
          other distributions permitted by applicable law on any Capital
          Stock of such Restricted Subsidiary owned by the Company or any
          other Restricted Subsidiary, (ii) pay any Indebtedness owed to
          the Company or any other Restricted Subsidiary, (iii) make loans
          or advances to the Company or any other Restricted Subsidiary or
          (iv) transfer any of its property or assets to the Company or any
          other Restricted Subsidiary.

                    The foregoing provisions shall not restrict any
          encumbrances or restrictions:

                    (i)    existing on the Closing Date this Indenture or
               any other agreements in effect on the Closing Date, and any
               extensions, refinancings, renewals or replacements of such
               agreements; provided that the encumbrances and restrictions
                           --------
               in any such extensions, refinancings, renewals or
               replacements are no less favorable in any material respect
               to the Holders than those encumbrances or restrictions that
               are then in effect and that are being extended, refinanced,
               renewed or replaced;

                    (ii)   existing under or by reason of applicable law,
               rule, regulation or order;

                    (iii)  existing with respect to any Person or the
               property or assets of such Person acquired by the Company or
               any Restricted Subsidiary, existing at the time of such
               acquisition and not incurred in contemplation thereof, which
               encumbrances or restrictions are not applicable to any
               Person or the property or assets of any Person other than
               such Person or the property or assets of such Person so
               acquired;

                    (iv)   in the case of clause (iv) of the first
               paragraph of this Section 4.05, (A) that restrict in a
               customary manner the subletting, assignment or transfer of
               any property or asset that is a lease, license, right-of-
               use, conveyance or contract or similar property or asset,
               (B) existing by virtue of any transfer of, agreement to
               transfer, option or right with respect to, or Lien on, any
               property or assets of the Company or any Restricted
               Subsidiary not otherwise prohibited by this Indenture, (C)
               arising or agreed to in the ordinary course of business, not
               relating to any Indebtedness, and that do not, individually
               or in the aggregate, detract from the value of property or
               assets of the Company or any Restricted Subsidiary in any
               manner material to the Company or any Restricted Subsidiary
               or (D) purchase money obligations (including, without
               limitation, Capitalized Leases and installment sales) for
               property acquired in the ordinary course of business that
               impose restrictions of the nature discussed in clause (iv)
               above on the property so acquired;

                    (v)    with respect to a Restricted Subsidiary and
               imposed pursuant to an agreement that has been entered into
               for the sale or disposition of all or substantially all of
               the Capital Stock of, or property and assets of, such
               Restricted Subsidiary;

                    (vi)   contained in the terms of any Indebtedness or
               any agreement pursuant to which such Indebtedness was issued
               if (A) (1) the encumbrances or restrictions apply only in
               the event of a payment default or a default with respect to
               a financial covenant contained in such Indebtedness or
               agreement or (2) the encumbrances or restrictions are
               similar in nature and substance to clause (iv) of the first
               paragraph of Section 4.04 hereof, as determined by the Board
               of Directors in good faith, (B) the encumbrances or
               restrictions are not materially more disadvantageous to the
               Holders of the Notes than is customary in comparable
               financings (as determined by the Company) and (C) the
               Company determines that any such encumbrances or
               restrictions will not materially affect the Company's
               ability to make principal or interest payments on the Notes;

                    (vii)  customary provisions in joint venture agreements
               and other similar agreements entered into in the ordinary
               course of business; and

                    (viii) any encumbrances or restrictions of the type
               referred to in clauses (i) through (iv) of the first
               paragraph of this Section 4.05 imposed by any amendments,
               modifications, renewals, restatements, increases,
               supplements, refundings, replacements or refinancings of the
               contracts referred to in clauses (i) through (vii) above;

          provided that such amendments, modifications, restatements, 
          --------
          renewals, increases, supplements, refundings, replacements or
          refinancings are, in the good faith judgment of the Company, not
          materially more disadvantageous to the Holders than those
          contained in the restriction prior to such amendment,
          modification, restatement, renewal, increase, supplement,
          refunding, replacement or refinancing.  Nothing contained in this
          Section 4.05 shall prevent the Company or any Restricted
          Subsidiary from (1) creating, incurring, assuming or suffering to
          exist any Liens otherwise permitted in Section 4.09 hereof or (2)
          restricting the sale or other disposition of property or assets
          of the Company or any of its Restricted Subsidiaries that secure
          Indebtedness of the Company or any of its Restricted
          Subsidiaries.

                    SECTION 4.06.  Limitation on the Issuance and Sale of 
                                   --------------------------------------
          Capital Stock of Restricted Subsidiaries.  The Company will not 
          ----------------------------------------
          sell, and will not permit any Restricted Subsidiary, directly or
          indirectly, to issue or sell, any shares of Capital Stock of a
          Restricted Subsidiary (including options, warrants or other
          rights to purchase shares of such Capital Stock) except (i) to
          the Company or a Wholly Owned Restricted Subsidiary; (ii)
          issuances of director's qualifying shares or sales to foreign
          nationals of shares of Capital Stock of foreign Restricted
          Subsidiaries, to the extent required by applicable law; (iii) if,
          immediately after giving effect to such issuance or sale, such
          Restricted Subsidiary would no longer constitute a Restricted
          Subsidiary and any Investment in such Person remaining after
          giving effect to such issuance or sale would have been permitted
          to be made under Section 4.04 hereof if made on the date of such
          issuance or sale; or (iv) issuances or sales of common stock of a
          Restricted Subsidiary, provided that the Company or any 
                                 --------
          Restricted Subsidiary applies an amount equal to the Net Cash
          Proceeds thereof in accordance with Section 4.11 hereof.

                    SECTION 4.07.  Limitation on Issuances of Guarantees by
                                   ----------------------------------------
          Restricted Subsidiaries.  The Company will not permit any 
          -----------------------
          Restricted Subsidiary, directly or indirectly, to Guarantee any
          Indebtedness of the Company which is pari passu with or
          subordinate in right of payment to the Notes ("Guaranteed 
                                                         ----------
          Indebtedness"), unless (i) such Restricted Subsidiary 
          ------------
          simultaneously executes and delivers a supplemental indenture to
          this Indenture providing for a Guarantee (a "Subsidiary 
                                                       ----------
          Guarantee") of payment of the Notes by such Restricted Subsidiary
          ---------
          and (ii) such Restricted Subsidiary waives and will not in any
          manner whatsoever claim or take the benefit or advantage of, any
          rights of reimbursement, indemnity or subrogation or any other
          rights against the Company or any other Restricted Subsidiary as
          a result of any payment by such Restricted Subsidiary under its
          Subsidiary Guarantee; provided that this paragraph shall not be 
                                --------
          applicable to any Guarantee of any Restricted Subsidiary that
          existed at the time such Person became a Restricted Subsidiary
          and was not Incurred in connection with, or in contemplation of,
          such Person becoming a Restricted Subsidiary.  If the Guaranteed
          Indebtedness is (A) pari passu in right of payment with the
          Notes, then the Guarantee of such Guaranteed Indebtedness shall
          be pari passu in right of payment with, or subordinated to, the
          Subsidiary Guarantee or (B) subordinated in right of payment to
          the Notes, then the Guarantee of such Guaranteed Indebtedness
          shall be subordinated in right of payment to the Subsidiary
          Guarantee at least to the extent that the Guaranteed Indebtedness
          is subordinated to the Notes.

                    Notwithstanding the foregoing, any Subsidiary Guarantee
          by a Restricted Subsidiary may provide by its terms that it shall
          be automatically and unconditionally released and discharged upon
          (i) any sale, exchange or transfer, to any Person not an
          Affiliate of the Company, of all of the Company's and each
          Restricted Subsidiary's Capital Stock in, or all or substantially
          all the assets of, such Restricted Subsidiary (which sale,
          exchange or transfer is not prohibited by this Indenture) or (ii)
          the release or discharge of the Guarantee which resulted in the
          creation of such Subsidiary Guarantee, except a discharge or
          release by or as a result of payment under such Guarantee.

                    SECTION 4.08.  Limitation on Transactions with 
                                   -------------------------------
          Shareholders and Affiliates.  The Company will not, and will not
          ---------------------------
          permit any Restricted Subsidiary to, directly or indirectly,
          enter into, renew or extend any transaction (including, without
          limitation, the purchase, sale, lease or exchange of property or
          assets, or the rendering of any service) with any Affiliate of
          the Company or any Restricted Subsidiary, except upon fair and
          reasonable terms no less favorable to the Company or such
          Restricted Subsidiary than could be obtained, at the time of such
          transaction or, if such transaction is pursuant to a written
          agreement, at the time of the execution of the agreement
          providing therefor, in a comparable arm's-length transaction with
          a Person that is not such an Affiliate.

                    The foregoing limitation does not limit, and shall not
          apply to:

                    (i)    transactions (A) approved by a majority of the
               disinterested members of the Board of Directors or (B) for
               which the Company or a Restricted Subsidiary delivers to the
               Trustee a written opinion of a nationally recognized
               investment banking firm or a nationally recognized firm
               having expertise in the specific area which is the subject
               of such determination stating that the transaction is fair
               to the Company or such Restricted Subsidiary from a
               financial point of view;

                    (ii)   any transaction solely between the Company and
               any of its Restricted Subsidiaries or solely between
               Restricted Subsidiaries;

                    (iii)  the payment of reasonable and customary regular
               fees to, and indemnity provided on behalf of, officers,
               directors, employees or consultants of the Company or its
               Restricted Subsidiaries;

                    (iv)   any payments or other transactions pursuant to
               any tax-sharing agreement between the Company and any other
               Person with which the Company files a consolidated tax
               return or with which the Company is part of a consolidated
               group for tax purposes; or

                    (v)    any Permitted Investments and Restricted
               Payments not prohibited by Section 4.04 hereof.

          Notwithstanding the foregoing, any transaction or series of
          related transactions covered by the first paragraph of this
          Section 4.08 and not covered by clauses (ii) through (v) of this
          paragraph the aggregate amount of which exceeds $2.0 million in
          value, must be approved or determined to be fair in the manner
          provided for in clause (i) (A) or (B) of this Section 4.08.

                    SECTION 4.09.  Limitation on Liens.  The Company will 
                                   -------------------
          not, and will not permit any Restricted Subsidiary to, create,
          incur, assume or suffer to exist any Lien on any of its assets or
          properties of any character (including, without limitation,
          licenses), or any shares of Capital Stock or Indebtedness of any
          Restricted Subsidiary, without making effective provision for all
          of the Notes and all other amounts due under this Indenture to be
          directly secured equally and ratably with (or, if the obligation
          or liability to be secured by such Lien is subordinated in right
          of payment to the Notes, prior to) the obligation or liability
          secured by such Lien.

                    The foregoing limitation does not apply to:

                    (i)    Liens existing on the Closing Date or required
               on the Closing Date to be provided in the future;

                    (ii)   Liens granted after the Closing Date on any
               assets or Capital Stock of the Company or its Restricted
               Subsidiaries created in favor of the Holders;

                    (iii)  Liens with respect to the assets of a Restricted
               Subsidiary granted by such Restricted Subsidiary to the
               Company or a Restricted Subsidiary to secure Indebtedness
               owing to the Company or such other Restricted Subsidiary;

                    (iv)   Liens securing Indebtedness which is Incurred to
               refinance secured Indebtedness which is permitted to be
               Incurred under clause (v) of the second paragraph of Section
               4.03 hereof; provided that such Liens do not extend to or 
                            --------
               cover any property or assets of the Company or any
               Restricted Subsidiary other than the property or assets
               securing the Indebtedness being refinanced;

                    (v)    Liens on any property or assets of Restricted
               Subsidiaries securing Indebtedness of Restricted
               Subsidiaries permitted under Section 4.03 hereof; or

                    (vi)   Permitted Liens.

                    SECTION 4.10.  Limitation on Sale-Leaseback 
                                   ----------------------------
          Transactions.  The Company will not, and will not permit any 
          ------------
          Restricted Subsidiary to, enter into any sale-leaseback
          transaction involving any of its assets or properties whether now
          owned or hereafter acquired, whereby the Company or a Restricted
          Subsidiary sells or transfers such assets or properties and then
          or thereafter leases such assets or properties or any part
          thereof or any other assets or properties which the Company or
          such Restricted Subsidiary, as the case may be, intends to use
          for substantially the same purpose or purposes as the assets or
          properties sold or transferred.

                    The foregoing restriction does not apply to any sale-
          leaseback transaction if:

                    (i)    the lease is for a period, including renewal
               rights, of not in excess of three years;

                    (ii)   the lease secures or relates to industrial
               revenue or pollution control bonds;

                    (iii)  the transaction is solely between the Company
               and any Wholly Owned Restricted Subsidiary or solely between
               Wholly Owned Restricted Subsidiaries; or

                    (iv)   the Company or such Restricted Subsidiary,
               within 12 months after the sale or transfer of any assets or
               properties is completed, applies an amount not less than the
               net proceeds received from such sale in accordance with
               clause (A) or (B) of the first paragraph of Section 4.11
               hereof.

                    SECTION 4.11.  Limitation on Asset Sales.  The Company
                                   -------------------------
          will not, and will not permit any Restricted Subsidiary to,
          consummate any Asset Sale, unless (i) the consideration received
          by the Company or such Restricted Subsidiary is at least equal to
          the fair market value of the assets sold or disposed of and (ii)
          at least 75% of the consideration received consists of cash or
          Temporary Cash Investments.  For purposes of this Section 4.11,
          the following are deemed to be cash:  (x) the principal amount or
          accreted value (whichever is larger) of Indebtedness of the
          Company or any Restricted Subsidiary with respect to which the
          Company or such Restricted Subsidiary has either (I) received a
          written release or (II) been released by operation of law, in
          either case, from all liability on such Indebtedness in
          connection with such Asset Sale and (y) securities received by
          the Company or any Restricted Subsidiary from the transferee that
          are promptly converted by the Company or such Restricted
          Subsidiary into cash. In the event and to the extent that the Net
          Cash Proceeds received by the Company or any of its Restricted
          Subsidiaries from one or more Asset Sales occurring on or after
          the Closing Date in any period of 12 consecutive months exceed
          10% of Adjusted Consolidated Net Tangible Assets (determined as
          of the date closest to the commencement of such 12-month period
          for which a consolidated balance sheet of the Company and its
          Subsidiaries has been filed with the Commission or provided to
          the Trustee pursuant to Section 4.18 hereof, then the Company
          shall or shall cause the relevant Restricted Subsidiary to (i)
          within 12 months after the date Net Cash Proceeds so received
          exceed 10% of Adjusted Consolidated Net Tangible Assets (A) apply
          an amount equal to such excess Net Cash Proceeds to permanently
          repay unsubordinated Indebtedness of the Company, or any
          Restricted Subsidiary providing a Subsidiary Guarantee pursuant
          to Section 4.07 hereof or Indebtedness of any other Restricted
          Subsidiary, in each case owing to a Person other than the Company
          or any of its Restricted Subsidiaries or (B) invest an equal
          amount, or the amount not so applied pursuant to clause (A) (or
          enter into a definitive agreement committing to so invest within
          12 months after the date of such agreement), (x) in property or
          assets (other than current assets) of a nature or type or that
          are used in a business (or in a Person (other than a natural
          person) having property and assets of a nature or type, or
          engaged in a business) similar or related to the nature or type
          of the property and assets of, or the business of, the Company
          and its Restricted Subsidiaries existing on the date of such
          investment (as determined in good faith by the Board of
          Directors, whose determination shall be conclusive and evidenced
          by a Board Resolution) or (y) in property or assets (other than
          current assets) related to the Telecommunications Business,
          including, without limitation, telecommunications switches and
          related equipment, services, leases, licenses, capacity and
          rights-of-use (or in a person (other than a natural person)
          having property or assets related to the Telecommunications
          Business, including, without limitation, telecommunications
          switches and related equipment, services, leases, licenses,
          capacity and rights-of-use) and (ii) apply (no later than the end
          of the 12-month period referred to in clause (i)) such excess Net
          Cash Proceeds (to the extent not applied pursuant to clause (i))
          as provided in the following paragraph of this Section 4.11.  The
          amount of such excess Net Cash Proceeds required to be applied
          (or to be committed to be applied) during such 12-month period as
          set forth in clause (i) of the preceding sentence and not applied
          as so required by the end of such period shall constitute "Excess
          Proceeds".

                    If, as of the first day of any calendar month, the
          aggregate amount of Excess Proceeds not theretofore subject to an
          Offer to Purchase pursuant to this Section 4.11 totals at least
          $20.0 million, the Company must commence, not later than the
          fifteenth Business Day of such month, and consummate an Offer to
          Purchase from the Holders on a pro rata basis, and an offer to
          purchase any outstanding Indebtedness with similar provisions
          requiring the Company to make an offer to purchase such
          Indebtedness, in an aggregate principal amount at maturity of
          Notes (or, if prior to February 15, 2003, the Accreted Value of
          the Notes) and such pari passu Indebtedness equal to (A) with
          respect to the Notes, the product of such Excess Proceeds
          multiplied by a fraction, the numerator of which is the
          outstanding principal amount at maturity of the Notes (or, if
          prior to February 15, 2003, the Accreted Value of the Notes) and
          the denominator of which is the sum of the outstanding principal
          amount at maturity of the Notes (or, if prior to February 15,
          2003, the Accreted Value of the Notes) and such pari passu
          Indebtedness (the product hereinafter referred to as the "Note
          Amount"), and (B) with respect to the pari passu Indebtedness,
          the excess of the Excess Proceeds over the Note Amount, at a
          purchase price equal to 100% of the Accreted Value of the Notes
          or such pari passu Indebtedness, as the case may be, on the
          relevant Payment Date or such other date set forth in the
          documentation governing the pari passu Indebtedness, plus, in
          each case, accrued interest (if any) to the Payment Date or such
          other date set forth in the documentation governing the pari
          passu Indebtedness. If the aggregate purchase price of the Notes
          tendered pursuant to the Offer to Purchase is less than the
          Excess Proceeds, the remaining will be available for use by the
          Company for general corporate purposes.  Upon the consummation of
          any Offer to Purchase in accordance with the terms of this
          Indenture, the amount of Net Cash Proceeds from Asset Sales
          subject to any future Offer to Purchase shall be deemed to be
          zero.

                    SECTION 4.12.  Repurchase of Notes upon a Change of 
                                   ------------------------------------
          Control.  The Company must commence, within 30 days of the 
          -------
          occurrence of a Change of Control, and consummate an Offer to
          Purchase for all Notes then outstanding, at a purchase price
          equal to 101% of the Accreted Value thereof on the relevant
          Payment Date, plus accrued interest (if any) to the Payment Date.

                    SECTION 4.13.  Existence.  Subject to Articles Four and
                                   ---------
          Five of this Indenture, the Company will do or cause to be done
          all things necessary to preserve and keep in full force and
          effect its existence and the existence of each of its Restricted
          Subsidiaries in accordance with the respective organizational
          documents of the Company and each such Subsidiary and the rights
          (whether pursuant to charter, partnership certificate, agreement,
          statute or otherwise), material licenses and franchises of the
          Company and each such Subsidiary; provided that the Company shall
                                            --------
          not be required to preserve any such right, license or franchise,
          or the existence of any Restricted Subsidiary, if the maintenance
          or preservation thereof is no longer desirable in the conduct of
          the business of the Company and its Restricted Subsidiaries taken
          as a whole.

                    SECTION 4.14.  Payment of Taxes and Other Claims.  The
                                   ---------------------------------
          Company will pay or discharge and shall cause each of its
          Subsidiaries to pay or discharge, or cause to be paid or
          discharged, before the same shall become delinquent (i) all
          material taxes, assessments and governmental charges levied or
          imposed upon (a) the Company or any such Subsidiary, (b) the
          income or profits of any such Subsidiary which is a corporation
          or (c) the property of the Company or any such Subsidiary and
          (ii) all material lawful claims for labor, materials and supplies
          that, if unpaid, might by law become a Lien upon the property of
          the Company or any such Subsidiary; provided that the Company 
                                              --------
          shall not be required to pay or discharge, or cause to be paid or
          discharged, any such tax, assessment, charge or claim the amount,
          applicability or validity of which is being contested in good
          faith by appropriate proceedings, for which adequate reserves
          have been established, and where the failure to effect such
          payment is not adverse in any material respect to the Holders.

                    SECTION 4.15.  Maintenance of Properties and Insurance. 
                                   ---------------------------------------
          The Company will cause all properties used or useful in the
          conduct of its business or the business of any of its Restricted
          Subsidiaries, to be maintained and kept in good condition, repair
          and working order and supplied with all necessary equipment and
          will cause to be made all necessary repairs, renewals,
          replacements, betterments and improvements thereof, all as in the
          judgment of the Company may be necessary so that the business
          carried on in connection therewith may be properly and
          advantageously conducted at all times; provided that nothing in 
                                                 --------
          this Section 4.15 shall prevent the Company or any such
          Subsidiary from discontinuing the use, operation or maintenance
          of any of such properties or disposing of any of them, if such
          discontinuance or disposal is, in the judgment of the Company,
          desirable in the conduct of the business of the Company or such
          Subsidiary.

                    The Company will provide or cause to be provided, for
          itself and its Restricted Subsidiaries, insurance (including
          appropriate self-insurance) against loss or damage of the kinds
          customarily insured against by corporations similarly situated
          and owning like properties, including, but not limited to,
          products liability insurance and public liability insurance, with
          reputable insurers or with the government of the United States of
          America, or an agency or instrumentality thereof, in such
          amounts, with such deductibles and by such methods as shall be
          customary for corporations similarly situated in the industry in
          which the Company or such Restricted Subsidiary, as the case may
          be, is then conducting business.

                    SECTION 4.16.  Notice of Defaults.  In the event that 
                                   ------------------
          the Company becomes aware of any Default or Event of Default, the
          Company, promptly after it becomes aware thereof, will give
          written notice thereof to the Trustee.

                    SECTION 4.17.  Compliance Certificates.  (a)  The 
                                   -----------------------
          Company shall deliver to the Trustee, within 90 days after the
          end of the Company's fiscal year, an Officers' Certificate
          stating whether or not the signers know of any Default or Event
          of Default that occurred during such fiscal year.  Such
          certificates shall contain a certification from the principal
          executive officer, principal financial officer or principal
          accounting officer of the Company that a review has been
          conducted of the activities of the Company and the Restricted
          Subsidiaries and the Company's and the Restricted Subsidiaries'
          performance under this Indenture and that the Company has
          complied with all conditions and covenants under this Indenture. 
          For purposes of this Section 4.17, such compliance shall be
          determined without regard to any period of grace or requirement
          of notice provided under this Indenture.  If they do know of such
          a Default or Event of Default, the certificate shall describe any
          such Default or Event of Default and its status.

                    (b)    The Company shall deliver to the Trustee, within
          90 days after the end of its fiscal year, a certificate signed by
          the Company's independent certified public accountants stating
          (i) that their audit examination has included a review of the
          terms of this Indenture and the Notes as they relate to
          accounting matters, (ii) that they have read the most recent
          Officers' Certificate delivered to the Trustee pursuant to
          paragraph (a) of this Section 4.17 and (iii) whether, in
          connection with their audit examination, anything came to their
          attention that caused them to believe that the Company was not in
          compliance with any of the terms, covenants, provisions or
          conditions of Article Four and Section 5.01 of this Indenture as
          they pertain to accounting matters and, if any Default or Event
          of Default has come to their attention, specifying the nature and
          period of existence thereof; provided that such independent 
                                       --------
          certified public accountants shall not be liable in respect of
          such statement by reason of any failure to obtain knowledge of
          any such Default or Event of Default that would not be disclosed
          in the course of an audit examination conducted in accordance
          with generally accepted auditing standards in effect at the date
          of such examination.

                    (c)    Within 90 days of the end of each of the
          Company's fiscal years, the Company shall deliver to the Trustee
          a list of all Significant Subsidiaries.  The Trustee shall have
          no duty with respect to any such list except to keep it on file
          and available for inspection by the Holders.

                    SECTION 4.18.  Commission Reports and Reports to 
                                   ---------------------------------
          Holders.  At all times from and after the earlier of (i) the date
          -------
          of the commencement of an Exchange Offer or the effectiveness of
          a Shelf Registration Statement (the "Registration") and (ii) the
                                               ------------
          date that is six months after the Closing Date, in either case,
          whether or not the Company is then required to file reports with
          the Commission, the Company shall deliver for filing with the
          Commission all such reports and other information as it would be
          required to file with the Commission by Section 13(a) or 15(d)
          under the Securities Exchange Act of 1934 if it were subject
          thereto.  All references herein to reports "filed" with the
          Commission shall be deemed to refer to the reports then most
          recently delivered for filing, whether or not accepted by the
          Commission.  The Company shall supply the Trustee and each Holder
          or shall supply to the Trustee for forwarding to each such
          Holder, without cost to such Holder, copies of such reports and
          other information.  In addition, at all times prior to the
          earlier of the date of the Registration and the date that is six
          months after the Closing Date, the Company shall, at its cost,
          deliver to each Holder of the Notes quarterly and annual reports
          substantially equivalent to those which would be required by the
          Exchange Act (or, in lieu thereof, the Registration Statement on
          Form S-1, S-3 or S-4 filed or to be filed with the Commission in
          connection with the Exchange Offer or the Shelf Registration
          Statement, if such Form and any amendments thereof contains
          comparable information).  In addition, at all times prior to the
          Registration, upon the request of any Holder or any prospective
          purchaser of the Notes designated by a Holder, the Company shall
          supply to such Holder or such prospective purchaser the
          information required under Rule 144A under the Securities Act.

                    SECTION 4.19.  Waiver of Stay, Extension or Usury Laws. 
                                   ---------------------------------------
          The Company covenants (to the extent that it may lawfully do so)
          that it will not at any time insist upon, or plead, or in any
          manner whatsoever claim or take the benefit or advantage of, any
          stay or extension law or any usury law or other law that would
          prohibit or forgive the Company from paying all or any portion of
          the principal of, premium, if any, or interest on the Notes as
          contemplated herein, wherever enacted, now or at any time
          hereafter in force, or that may affect the covenants or the
          performance of this Indenture; and (to the extent that it may
          lawfully do so) the Company hereby expressly waives all benefit
          or advantage of any such law and covenants that it will not
          hinder, delay or impede the execution of any power herein granted
          to the Trustee, but will suffer and permit the execution of every
          such power as though no such law had been enacted.

                                     ARTICLE FIVE
                                SUCCESSOR CORPORATION

                    SECTION 5.01.  When Company May Merge, Etc.  The 
                                   ----------------------------
          Company shall not consolidate with, merge with or into, or sell,
          convey, transfer, lease or otherwise dispose of all or
          substantially all of its property and assets (as an entirety or
          substantially an entirety in one transaction or a series of
          related transactions) to, any Person or permit any Person to
          merge with or into the Company unless:

                    (i)    the Company shall be the continuing Person, or
               the Person (if other than the Company) formed by such
               consolidation or into which the Company is merged or that
               acquired or leased such property and assets of the Company
               shall be a corporation organized and validly existing under
               the laws of the United States of America or any jurisdiction
               thereof and shall expressly assume, by a supplemental
               indenture, executed and delivered to the Trustee, all of the
               obligations of the Company on all of the Notes and under
               this Indenture;

                    (ii)   immediately after giving effect to such
               transaction, no Default or Event of Default shall have
               occurred and be continuing;

                    (iii)  immediately after giving effect to such
               transaction on a pro forma basis, (A) the Company or any
               Person becoming the successor obligor of the Notes, as the
               case may be, shall have a Consolidated Net Worth equal to or
               greater than the Consolidated Net Worth of the Company
               immediately prior to such transaction; or (B) the Company or
               any Person becoming the successor obligor of the Notes, as
               the case may be, shall have a Consolidated Leverage Ratio no
               more than the greater of (I) 6:1 and (II) the Consolidated
               Leverage Ratio of the Company immediately prior to such
               transaction; provided that this clause (iii) shall not apply
                            --------
               to a consolidation or merger with or into a Wholly Owned
               Restricted Subsidiary with a positive net worth; provided 
                                                                --------
               that, in connection with any such merger or consolidation,
               no consideration (other than Capital Stock (other than
               Disqualified Stock) in the surviving Person or the Company)
               shall be issued or distributed to the stockholders of the
               Company; and

                    (iv)   the Company delivers to the Trustee an Officers'
               Certificate (attaching the arithmetic computations to
               demonstrate compliance with clause (iii) above) and Opinion
               of Counsel, in each case stating that such consolidation,
               merger or transfer and such supplemental indenture complies
               with this provision and that all conditions precedent
               provided for herein relating to such transaction have been
               complied with;

          provided, however, that clause (iii) of this Section 5.01 does 
          --------  -------
          not apply if, in the good faith determination of the Board of
          Directors of the Company, whose determination shall be evidenced
          by a Board Resolution, the principal purpose of such transaction
          is to change the state of incorporation of the Company; and that
          any such transaction shall not have as one of its purposes the
          evasion of the foregoing limitations.

                    SECTION 5.02.  Successor Substituted.  Upon any 
                                   ---------------------
          consolidation or merger, or any sale, conveyance, transfer or
          other disposition of all or substantially all of the property and
          assets of the Company in accordance with Section 5.01 of this
          Indenture, the successor Person formed by such consolidation or
          into which the Company is merged or to which such sale,
          conveyance, transfer or other disposition is made shall succeed
          to, and be substituted for, and may exercise every right and
          power of, the Company under this Indenture with the same effect
          as if such successor Person had been named as the Company herein.


                                     ARTICLE SIX
                                 DEFAULT AND REMEDIES

                    SECTION 6.01.  Events of Default.  An "Event of 
                                   -----------------       --------
          Default" shall occur with respect to the Notes if:
          -------

                    (a)    the Company defaults in the payment of principal
               of (or premium, if any, on) any Note when the same becomes
               due and payable at maturity, upon acceleration, redemption
               or otherwise;

                    (b)    the Company defaults in the payment of interest
               on any Note when the same becomes due and payable, and such
               default continues for a period of 30 days;

                    (c)    the Company defaults in the performance of or
               breaches any other covenant or agreement of the Company in
               this Indenture or under the Notes (other than a default
               specified in clause (a) or (b) of this Section 6.01 and such
               default or breach continues for a period of 30 consecutive
               days after written notice by the Trustee to the Company or
               to the Company and the Trustee by the Holders of 25% or more
               in aggregate principal amount of the Notes;

                    (d)    the Company fails to make or consummate an Offer
               to Purchase in accordance with Section 4.11 hereof;

                    (e)    the Company fails to make or consummate an Offer
               to Purchase in accordance with the provisions of Section
               4.12 hereof;

                    (f)    there occurs with respect to any issue or issues
               of Indebtedness of the Company or any Significant Subsidiary
               having an outstanding principal amount at maturity of $10
               million or more in the aggregate for all such issues of all
               such Persons, whether such Indebtedness now exists or shall
               hereafter be created, (I) an event of default that has
               caused the holder thereof to declare such Indebtedness to be
               due and payable prior to its Stated Maturity and such
               Indebtedness has not been discharged in full or such
               acceleration has not been rescinded or annulled within 30
               days of such acceleration and/or (II) the failure to make a
               principal payment at the final (but not any interim) fixed
               maturity and such defaulted payment shall not have been
               made, waived or extended within 30 days of such payment
               default;

                    (g)    any final judgment or order (not covered by
               insurance) for the payment of money in excess of $10 million
               in the aggregate (treating any deductibles, self-insurance
               or retention as not so covered) shall be rendered against
               the Company or any Significant Subsidiary and shall not be
               paid or discharged, and there shall be any period of 30
               consecutive days following entry of the final judgment or
               order that causes the aggregate amount for all such final
               judgments or orders outstanding and not paid or discharged
               against the Company or any of its Significant Subsidiaries
               to exceed $10 million during which a stay of enforcement of
               such final judgment or order, by reason of a pending appeal
               or otherwise, shall not be in effect;

                    (h)    a court having jurisdiction in the premises
               enters a decree or order for (A) relief in respect of the
               Company or any Significant Subsidiary in an involuntary case
               under any applicable bankruptcy, insolvency or other similar
               law now or hereafter in effect, (B) appointment of a
               receiver, liquidator, assignee, custodian, trustee,
               sequestrator or similar official of the Company or any
               Significant Subsidiary or for all or substantially all of
               the property and assets of the Company or any Significant
               Subsidiary or (C) the winding up or liquidation of the
               affairs of the Company or any Significant Subsidiary and, in
               each case, such decree or order shall remain unstayed and in
               effect for a period of 30 consecutive days; or

                    (i)    the Company or any Significant Subsidiary (A)
               commences a voluntary case under any applicable bankruptcy,
               insolvency or other similar law now or hereafter in effect,
               or consents to the entry of an order for relief in an
               involuntary case under any such law, (B) consents to the
               appointment of or taking possession by a receiver,
               liquidator, assignee, custodian, trustee, sequestrator or
               similar official of the Company or any Significant
               Subsidiary or for all or substantially all of the property
               and assets of the Company or any Significant Subsidiary or
               (C) effects any general assignment for the benefit of
               creditors.

                    SECTION 6.02.  Acceleration.  If an Event of Default 
                                   ------------
          (other than an Event of Default specified in clause (h) or (i) of
          Section 6.01 that occurs with respect to the Company) occurs and
          is continuing under this Indenture, the Trustee or the Holders of
          at least 25% in aggregate principal amount of the Notes then
          outstanding, by written notice to the Company (and to the Trustee
          if such notice is given by the Holders), may, and the Trustee at
          the request of such Holders shall, declare the Accreted Value of,
          premium, if any, and accrued interest on the Notes to be
          immediately due and payable.  Upon a declaration of acceleration,
          such Accreted Value of, premium, if any, and accrued interest
          shall be immediately due and payable.  In the event of a
          declaration of acceleration because an Event of Default set forth
          in clause (f) of Section 6.01 has occurred and is continuing,
          such declaration of acceleration shall be automatically rescinded
          and annulled if the event of default triggering such Event of
          Default pursuant to clause (f) shall be remedied or cured by the
          Company or the relevant Significant Subsidiary or waived by the
          holders of the relevant Indebtedness within 60 days after the
          declaration of acceleration with respect thereto.  If an Event of
          Default specified in clause (h) or (i) of Section 6.01 occurs
          with respect to the Company, the Accreted Value of, premium, if
          any, and accrued interest on the Notes then outstanding shall
          ipso facto become and be immediately due and payable without any
          declaration or other act on the part of the Trustee or any
          Holder.

                    At any time after such a declaration of acceleration,
          but before a judgment or decree for the payment of the money due
          has been obtained by the Trustee, the Holders of at least a
          majority in principal amount at maturity of the outstanding Notes
          by written notice to the Company and to the Trustee may waive all
          past Defaults and rescind and annul such declaration of
          acceleration and its consequences if (a) the Company has paid or
          deposited with the Trustee a sum sufficient to pay (i) all sums
          paid or advanced by the Trustee hereunder and the reasonable
          compensation, expenses, disbursements and advances of the
          Trustee, its agents and counsel, (ii) all overdue interest on all
          Notes, (iii) the principal of and premium, if any, on any Notes
          that have become due otherwise than by such declaration or
          occurrence of acceleration and interest thereon at the rate
          prescribed therefor by such Notes, and (iv) to the extent that
          payment of such interest is lawful, interest upon overdue
          interest at the rate prescribed therefor by such Notes, (b) all
          existing Events of Default, other than the non-payment of the
          Accreted Value of, premium, if any, and accrued interest on the
          Notes that have become due solely by such declaration of
          acceleration, have been cured or waived and (c) the rescission
          would not conflict with any judgment or decree of a court of
          competent jurisdiction.

                    SECTION 6.03.  Other Remedies.  If an Event of Default
                                   --------------
          occurs and is continuing, the Trustee may pursue any available
          remedy by proceeding at law or in equity to collect the payment
          of principal of, premium, if any, or interest on the Notes or to
          enforce the performance of any provision of the Notes or this
          Indenture.

                    The Trustee may maintain a proceeding even if it does
          not possess any of the Notes or does not produce any of them in
          the proceeding.

                    SECTION 6.04.  Waiver of Past Defaults.  Subject to 
                                   -----------------------
          Sections 6.02, 6.07 and 9.02, the Holders of at least a majority
          in principal amount at maturity of the outstanding Notes, by
          notice to the Trustee, may waive an existing Default or Event of
          Default and its consequences, except a Default in the payment of
          the Accreted Value of, premium, if any, or accrued interest on
          any Note as specified in clause (a) or (b) of Section 6.01 or in
          respect of a covenant or provision of this Indenture which cannot
          be modified or amended without the consent of the holder of each
          outstanding Note affected.  Upon any such waiver, such Default
          shall cease to exist, and any Event of Default arising therefrom
          shall be deemed to have been cured, for every purpose of this
          Indenture; but no such waiver shall extend to any subsequent or
          other Default or Event of Default or impair any right consequent
          thereto.

                    SECTION 6.05.  Control by Majority.  The Holders of at
                                   -------------------
          least a majority in aggregate principal amount at maturity of the
          outstanding Notes may direct the time, method and place of
          conducting any proceeding for any remedy available to the Trustee
          or exercising any trust or power conferred on the Trustee.
          However, the Trustee may refuse to follow any direction that
          conflicts with law or this Indenture, that may involve the
          Trustee in personal liability, or that the Trustee determines in
          good faith may be unduly prejudicial to the rights of Holders of
          Notes not joining in the giving of such direction and may take
          any other action it deems proper that is not inconsistent with
          any such direction received from Holders of Notes.

                    SECTION 6.06.  Limitation on Suits.  A Holder may not 
                                   -------------------
          institute any proceeding, judicial or otherwise, with respect to
          this Indenture or the Notes, or for the appointment of a receiver
          or trustee, or for any other remedy hereunder unless:

                    (i)    such Holder has previously given to the Trustee
               written notice of a continuing Event of Default;

                    (ii)   the Holders of at least 25% in aggregate
               principal amount at maturity of outstanding Notes shall have
               made written request to the Trustee to pursue the remedy;

                    (iii)  such Holder or Holders have offered to the
               Trustee indemnity satisfactory to the Trustee against any
               costs, liabilities or expenses to be incurred in compliance
               with such request;

                    (iv)   the Trustee has failed to comply with the
               request within 60 days after receipt of the request and the
               offer of indemnity; and

                    (v)    during such 60-day period, the Holders of a
               majority in aggregate principal amount at maturity of the
               outstanding Notes have not given the Trustee a direction
               that is inconsistent with such request.

                    For purposes of Section 6.05 of this Indenture and this
          Section 6.06, the Trustee shall comply with TIA Section 316(a) in
          making any determination of whether the Holders of the required
          aggregate principal amount at maturity of outstanding Notes have
          concurred in any request or direction of the Trustee to pursue
          any remedy available to the Trustee or the Holders with respect
          to this Indenture or the Notes or otherwise under the law.

                    A Holder may not use this Indenture to prejudice the
          rights of another Holder or to obtain a preference or priority
          over such other Holder.

                    SECTION 6.07.  Rights of Holders to Receive Payment.  
                                   ------------------------------------
          Notwithstanding any other provision of this Indenture, the right
          of any Holder of a Note to receive payment of principal of,
          premium, if any, or interest on such Holder's Note on or after
          the respective due dates expressed on such Note, or to bring suit
          for the enforcement of any such payment on or after such
          respective dates, shall not be impaired or affected without the
          consent of such Holder.

                    SECTION 6.08.  Collection Suit by Trustee.  If an Event
                                   --------------------------
          of Default in payment of principal, premium or interest specified
          in clause (a) or (b) of Section 6.01 occurs and is continuing,
          the Trustee may recover judgment in its own name and as trustee
          of an express trust against the Company or any other obligor of
          the Notes for the whole amount of principal, premium, if any, and
          accrued interest remaining unpaid, together with interest on
          overdue principal, premium, if any, and, to the extent that
          payment of such interest is lawful, interest on overdue
          installments of interest, in each case at the rate specified in
          the Notes, and such further amount as shall be sufficient to
          cover the costs and expenses of collection, including the
          reasonable compensation, expenses, disbursements and advances of
          the Trustee, its agents and counsel.

                    SECTION 6.09.  Trustee May File Proofs of Claim.  The 
                                   --------------------------------
          Trustee may file such proofs of claim and other papers or
          documents as may be necessary or advisable in order to have the
          claims of the Trustee (including any claim for the reasonable
          compensation, expenses, disbursements and advances of the
          Trustee, its agents and counsel, and any other amounts due the
          Trustee under Section 7.07) and the Holders allowed in any
          judicial proceedings relative to the Company (or any other
          obligor of the Notes), its creditors or its property and shall be
          entitled and empowered to collect and receive any monies,
          securities or other property payable or deliverable upon
          conversion or exchange of the Notes or upon any such claims and
          to distribute the same, and any custodian, receiver, assignee,
          trustee, liquidator, sequestrator or other similar official in
          any such judicial proceeding is hereby authorized by each Holder
          to make such payments to the Trustee and, in the event that the
          Trustee shall consent to the making of such payments directly to
          the Holders, to pay to the Trustee any amount due to it for the
          reasonable compensation, expenses, disbursements and advances of
          the Trustee, its agent and counsel, and any other amounts due the
          Trustee under Section 7.07.  Nothing herein contained shall be
          deemed to empower the Trustee to authorize or consent to, or
          accept or adopt on behalf of any Holder, any plan of
          reorganization, arrangement, adjustment or composition affecting
          the Notes or the rights of any Holder thereof, or to authorize
          the Trustee to vote in respect of the claim of any Holder in any
          such proceeding.

                    SECTION 6.10.  Priorities.  If the Trustee collects any
                                   ----------
          money pursuant to this Article Six, it shall pay out the money in
          the following order:

                    First:    to the Trustee for all amounts due under
               Section 7.07;

                    Second:   to Holders for amounts then due and unpaid
               for principal of, premium, if any, and interest on the Notes
               in respect of which or for the benefit of which such money
               has been collected, ratably, without preference or priority
               of any kind, according to the amounts due and payable on
               such Notes for principal, premium, if any, and interest,
               respectively; and

                    Third:    to the Company or any other obligors of the
               Notes, as their interests may appear, or as a court of
               competent jurisdiction may direct.

                    The Trustee, upon prior written notice to the Company,
          may fix a record date and payment date for any payment to Holders
          pursuant to this Section 6.10.

                    SECTION 6.11.  Undertaking for Costs.  In any suit for
                                   ---------------------
          the enforcement of any right or remedy under this Indenture or in
          any suit against the Trustee for any action taken or omitted by
          it as Trustee, a court may require any party litigant in such
          suit to file an undertaking to pay the costs of the suit, and the
          court may assess reasonable costs, including reasonable
          attorneys' fees, against any party litigant in the suit having
          due regard to the merits and good faith of the claims or defenses
          made by the party litigant.  This Section 6.11 does not apply to
          a suit by the Trustee, a suit by a Holder pursuant to Section
          6.07 of this Indenture, or a suit by Holders of more than 10% in
          principal amount at maturity of the outstanding Notes.

                    SECTION 6.12.  Restoration of Rights and Remedies.  If
                                   ----------------------------------
          the Trustee or any Holder has instituted any proceeding to
          enforce any right or remedy under this Indenture and such
          proceeding has been discontinued or abandoned for any reason, or
          has been determined adversely to the Trustee or to such Holder,
          then, and in every such case, subject to any determination in
          such proceeding, the Company, the Trustee and the Holders shall
          be restored severally and respectively to their former positions
          hereunder and thereafter all rights and remedies of the Company,
          the Trustee and the Holders shall continue as though no such
          proceeding had been instituted.

                    SECTION 6.13.  Rights and Remedies Cumulative.  Except
                                   ------------------------------
          as otherwise provided with respect to the replacement or payment
          of mutilated, destroyed, lost or wrongfully taken Notes in
          Section 2.09, no right or remedy herein conferred upon or
          reserved to the Trustee or to the Holders is intended to be
          exclusive of any other right or remedy, and every right and
          remedy shall, to the extent permitted by law, be cumulative and
          in addition to every other right and remedy given hereunder or
          now or hereafter existing at law or in equity or otherwise.  The
          assertion or employment of any right or remedy hereunder, or
          otherwise, shall not prevent the concurrent assertion or
          employment of any other appropriate right or remedy.

                    SECTION 6.14.  Delay or Omission Not Waiver.  No delay
                                   ----------------------------
          or omission of the Trustee or of any Holder to exercise any right
          or remedy accruing upon any Event of Default shall impair any
          such right or remedy or constitute a waiver of any such Event of
          Default or an acquiescence therein.  Every right and remedy given
          by this Article Six or by law to the Trustee or to the Holders
          may be exercised from time to time, and as often as may be deemed
          expedient, by the Trustee or by the Holders, as the case may be.


                                    ARTICLE SEVEN
                                       TRUSTEE

                    SECTION 7.01.  General.  The duties and 
                                   -------
          responsibilities of the Trustee shall be as provided by the TIA
          and as set forth herein.  Notwithstanding the foregoing, no
          provision of this Indenture shall require the Trustee to expend
          or risk its own funds or otherwise incur any financial liability
          in the performance of any of its duties hereunder, or in the
          exercise of any of its rights or powers, if it shall have
          reasonable grounds for believing that repayment of such funds or
          adequate indemnity against such risk or liability is not
          reasonably assured to it.  Whether or not therein expressly so
          provided, every provision of this Indenture relating to the
          conduct or affecting the liability of or affording protection to
          the Trustee shall be subject to the provisions of this Article
          Seven.

                    SECTION 7.02.  Certain Rights of Trustee.  Subject to 
                                   -------------------------
          TIA Sections 315(a) through (d):

                    (i)  the Trustee may rely and shall be protected in
               acting or refraining from acting upon any resolution,
               certificate, statement, instrument, opinion, report, notice,
               request, direction, consent, order, bond, debenture, note,
               other evidence of indebtedness or other paper or document
               believed by it to be genuine and to have been signed or
               presented by the proper person.  The Trustee need not
               investigate any fact or matter stated in the document and
               may in good faith conclusively rely as to the truth of the
               statements and the correctness of the opinions therein;

                    (ii) before the Trustee acts or refrains from acting,
               it may require an Officers' Certificate or an Opinion of
               Counsel, which shall conform to Section 10.04.  The Trustee
               shall not be liable for any action it takes or omits to take
               in good faith in reliance on such certificate, opinion
               and/or an accountants' certificate if required under the
               TIA;

                    (iii)     the Trustee may act through its attorneys and
               agents and shall not be responsible for the misconduct or
               negligence of any agent appointed with due care;

                    (iv) the Trustee shall be under no obligation to
               exercise any of the rights or powers vested in it by this
               Indenture at the request or direction of any of the Holders,
               unless such Holders shall have offered to the Trustee
               security or indemnity reasonably satisfactory to it against
               the costs, expenses and liabilities that might be incurred
               by it in compliance with such request or direction;

                    (v)  the Trustee shall not be liable for any action it
               takes or omits to take in good faith that it believes to be
               authorized or within its rights or powers or for any action
               it takes or omits to take in accordance with the direction
               of the Holders of a majority in principal amount at maturity
               of the Outstanding Notes relating to the time, method and
               place of conducting any proceeding for any remedy available
               to the Trustee, or exercising any trust or power conferred
               upon the Trustee, under this Indenture; provided that the 
                                                       --------
               Trustee's conduct does not constitute gross negligence or
               bad faith;

                    (vi) whenever in the administration of this Indenture
               the Trustee shall deem it desirable that a making be proved
               or established prior to taking, suffering or omitting any
               action hereunder, the Trustee (unless other evidence be
               herein specifically prescribed) may, in the absence of bad
               faith on its part, rely upon an Officer's Certificate; and

                    (vii)     the Trustee shall not be bound to make any
               investigation into the facts or matters stated in any
               resolution, certificate, statement, instrument, opinion,
               report, notice, request, direction, consent, order, bond,
               debenture, note, other evidence of indebtedness or other
               paper or document, but the Trustee, in its discretion, may
               make such further inquiry or investigation into such facts
               or matters as it may see fit, and, if the Trustee shall
               determine to make such further inquiry or investigation, it
               shall be entitled to examine the books, records and premises
               of the Company personally or by agent or attorney.

                    SECTION 7.03.  Individual Rights of Trustee.  The 
                                   ----------------------------
          Trustee, in its individual or any other capacity, may become the
          owner or pledgee of Notes and may otherwise deal with the Company
          or its Affiliates with the same rights it would have if it were
          not the Trustee.  Any Agent may do the same with like rights. 
          However, the Trustee is subject to TIA Sections 310(b) and 311.

                    SECTION 7.04.  Trustee's Disclaimer.  The Trustee 
                                   --------------------
          (i) makes no representation as to the validity or adequacy of
          this Indenture or the Notes, (ii) shall not be accountable for
          the Company's use or application of the proceeds from the Notes
          and (iii) shall not be responsible for any statement in the Notes
          other than its certificate of authentication.

                    SECTION 7.05.  Notice of Default.  If any Default or 
                                   -----------------
          any Event of Default occurs and is continuing and if such Default
          or Event of Default is known to a Responsible Officer of the
          Trustee, the Trustee shall mail to each Holder in the manner and
          to the extent provided in TIA Section 313(c) notice of the
          Default or Event of Default within 90 days after it occurs,
          unless such Default or Event of Default has been cured; provided,
                                                                  --------
          however, that, except in the case of a default in the payment of
          -------
          the principal of, premium, if any, or interest on any Note, the
          Trustee shall be protected in withholding such notice if and so
          long as the board of directors, the executive committee or a
          trust committee of directors and/or Responsible Officers of the
          Trustee in good faith determine that the withholding of such
          notice is in the interest of the Holders.

                    SECTION 7.06.  Reports by Trustee to Holders.  Within 
                                   -----------------------------
          60 days after each May 15, beginning with May 15, 1998, the
          Trustee shall mail to each Holder as provided in TIA Section
          313(c) a brief report that complies with TIA Section 313(a) dated
          as of such May 15, if required by TIA Section 313(a).

                    SECTION 7.07.  Compensation and Indemnity.  The Company
                                   --------------------------
          shall pay to the Trustee such compensation as shall be agreed
          upon in writing for its services.  The compensation of the
          Trustee shall not be limited by any law on compensation of a
          trustee of an express trust.  The Company shall reimburse the
          Trustee upon request for all reasonable out-of-pocket expenses
          and advances incurred or made by the Trustee.  Such expenses
          shall include the reasonable compensation and expenses of the
          Trustee's agents and counsel.

                    The Company shall indemnify the Trustee for, and hold
          it harmless against, any loss or liability or expense incurred by
          it without negligence or bad faith on its part in connection with
          the acceptance or administration of this Indenture and its duties
          under this Indenture and the Notes, including the costs and
          expenses of defending itself against any claim or liability and
          of complying with any process served upon it or any of its
          officers in connection with the exercise or performance of any of
          its powers or duties under this Indenture and the Notes.

                    To secure the Company's payment obligations in this
          Section 7.07, the Trustee shall have a lien prior to the Notes on
          all money or property held or collected by the Trustee, in its
          capacity as Trustee, except money or property held in trust to
          pay principal of, premium, if any, and interest on particular
          Notes.
                    If the Trustee incurs expenses or renders services
          after the occurrence of an Event of Default specified in clause
          (h) or (i) of Section 6.01, the expenses and the compensation for
          the services will be intended to constitute expenses of
          administration under Title 11 of the United States Bankruptcy
          Code or any applicable federal or state law for the relief of
          debtors.

                    SECTION 7.08.  Replacement of Trustee.  A resignation 
                                   ----------------------
          or removal of the Trustee and appointment of a successor Trustee
          shall become effective only upon the successor Trustee's
          acceptance of appointment as provided in this Section 7.08.

                    The Trustee may resign at any time by so notifying the
          Company in writing at least 30 days prior to the date of the
          proposed resignation.  The Holders of a majority in principal
          amount at maturity of the outstanding Notes may remove the
          Trustee by so notifying the Trustee in writing and may appoint a
          successor Trustee with the consent of the Company.  The Company
          may at any time remove the Trustee, by Company Order given at
          least 30 days prior to the date of the proposed removal.

                    If the Trustee resigns or is removed, or if a vacancy
          exists in the office of Trustee for any reason, the Company shall
          promptly appoint a successor Trustee.  Within one year after the
          successor Trustee takes office, the Holders of a majority in
          principal amount at maturity of the outstanding Notes may appoint
          a successor Trustee to replace the successor Trustee appointed by
          the Company.  If the successor Trustee does not deliver its
          written acceptance required by the next succeeding paragraph of
          this Section 7.08 within 30 days after the retiring Trustee
          resigns or is removed, the retiring Trustee, the Company or the
          Holders of a majority in principal amount at maturity of the
          outstanding Notes may petition any court of competent
          jurisdiction for the appointment of a successor Trustee.

                    A successor Trustee shall deliver a written acceptance
          of its appointment to the retiring Trustee and to the Company. 
          Immediately after the delivery of such written acceptance,
          subject to the lien provided in Section 7.07, (i) the retiring
          Trustee shall transfer all property held by it as Trustee to the
          successor Trustee, (ii) the resignation or removal of the
          retiring Trustee shall become effective and (iii) the successor
          Trustee shall have all the rights, powers and duties of the
          Trustee under this Indenture.  A successor Trustee shall mail
          notice of its succession to each Holder.

                    If the Trustee is no longer eligible under Section
          7.10, any Holder who satisfies the requirements of TIA Section
          310(b) may petition any court of competent jurisdiction for the
          removal of the Trustee and the appointment of a successor
          Trustee.

                    The Company shall give notice of any resignation and
          any removal of the Trustee and each appointment of a successor
          Trustee to all Holders.  Each notice shall include the name of
          the successor Trustee and the address of its Corporate Trust
          Office.

                    Notwithstanding replacement of the Trustee pursuant to
          this Section 7.08, the Company's obligation under Section 7.07
          shall continue for the benefit of the retiring Trustee.

                    SECTION 7.09.  Successor Trustee by Merger, Etc.  If 
                                   ---------------------------------
          the Trustee consolidates with, merges or converts into, or
          transfers all or substantially all of its corporate trust
          business to, another corporation or national banking association,
          the resulting, surviving or transferee corporation or national
          banking association without any further act shall be the
          successor Trustee with the same effect as if the successor
          Trustee had been named as the Trustee herein.

                    SECTION 7.10.  Eligibility.  This Indenture shall 
                                   -----------
          always have a Trustee who satisfies the requirements of TIA
          Sections 310(a)(1) and 310(a)(5).  The Trustee shall have a
          combined capital and surplus of at least $25,000,000 as set forth
          in its most recent published annual report of condition.

                    SECTION 7.11.  Money Held in Trust.  The Trustee shall
                                   -------------------
          not be liable for  interest on any money received by it except as
          the Trustee may agree with the Company.  Money held in trust by
          the Trustee need not be segregated from other funds except to the
          extent required by law and except for money held in trust under
          Article Eight of this Indenture.

                    SECTION 7.12.  Withholding Taxes.  The Trustee, as 
                                   -----------------
          agent for the Company, shall exclude and withhold from each
          payment of principal and interest and other amounts due hereunder
          or under the Notes any and all withholding taxes applicable
          thereto as required by law.  The Trustee agrees to act as such
          withholding agent and, in connection therewith, whenever any
          present or future taxes or similar charges are required to be
          withheld with respect to any amounts payable in respect of the
          Notes, to withhold such amounts and timely pay the same to the
          appropriate authority in the name of and on behalf of the Holders
          of the Notes, that it will file any necessary withholding tax
          returns or statements when due, and that, as promptly as possible
          after the payment thereof, it will deliver to each Holder of a
          Note appropriate documentation showing the payment thereof,
          together with such additional documentary evidence as such
          Holders may reasonably request from time to time.


                                    ARTICLE EIGHT
                                DISCHARGE OF INDENTURE

                    SECTION 8.01.  Termination of the Company's 
                                   ----------------------------
          Obligations.  Except as otherwise provided in this Section 8.01,
          -----------
          the Company may terminate its obligations under the Notes and
          this Indenture if:

                    (i)  all Notes previously authenticated and delivered
               (other than destroyed, lost or stolen Notes that have been
               replaced or Notes that are paid pursuant to Section 4.01 or
               Notes for whose payment money or securities have theretofore
               been held in trust and thereafter repaid to the Company, as
               provided in Section 8.05) have been delivered to the Trustee
               for cancellation and the Company has paid all sums payable
               by it hereunder; or

                    (ii) (A) all the Notes mature within one year or all of
               them are to be called for redemption within one year under
               arrangements satisfactory to the Trustee for giving the
               notice of redemption, (B) the Company deposits in trust with
               the Trustee during such one-year period, under the terms of
               an irrevocable trust agreement in form and substance
               satisfactory to the Trustee, as trust funds solely for the
               benefit of the Holders for that purpose, money or U.S.
               Government Obligations sufficient (in the opinion of a
               nationally recognized firm of independent public accountants
               expressed in a written certification thereof delivered to
               the Trustee), without consideration of any reinvestment of
               any interest thereon, to pay principal, premium, if, any,
               and interest on the Notes to maturity or redemption, as the
               case may be, and to pay all other sums payable by it
               hereunder, (C) no Default or Event of Default with respect
               to the Notes shall have occurred and be continuing on the
               date of such deposit, (D) such deposit will not result in a
               breach or violation of, or constitute a default under, this
               Indenture or any other agreement or instrument to which the
               Company is a party or by which it is bound and (E) the
               Company has delivered to the Trustee an Officers'
               Certificate and an Opinion of Counsel, in each case stating
               that all conditions precedent provided for herein relating
               to the satisfaction and discharge of this Indenture have
               been complied with.

                    With respect to the foregoing clause (i), the Company's
          obligations under Section 7.07 shall survive.  With respect to
          the foregoing clause (ii), the Company's obligations in Sections
          2.02, 2.03, 2.04, 2.05, 2.06, 2.07, 2.08, 2.09, 2.14, 4.01, 4.02,
          7.07, 7.08, 8.04, 8.05 and 8.06 shall survive until the Notes are
          no longer outstanding.  Thereafter, only the Company's
          obligations in Sections 7.07, 8.05 and 8.06 shall survive.  After
          any such irrevocable deposit, the Trustee upon request shall
          acknowledge in writing the discharge of the Company's
          obligations, as the case may be, under the Notes and this
          Indenture except for those surviving obligations specified above.

                    SECTION 8.02.  Defeasance and Discharge of Indenture. 
                                   -------------------------------------
          The Company will be deemed to have paid and will be discharged
          from any and all obligations in respect of the Notes on the 123rd
          day after the deposit referred to below, and the provisions of
          this Indenture will no longer be in effect with respect to the
          Notes (except for, among other matters, certain obligations to
          register the transfer or exchange of the Notes, to replace
          stolen, lost or mutilated Notes, to maintain paying agencies and
          to hold monies for payment in trust) if, among other things,

                    (A)  the Company has deposited with the Trustee, in
               trust, money and/or U.S. Government Obligations that through
               the payment of interest and principal in respect thereof in
               accordance with their terms will provide money in an amount
               sufficient to pay the principal of, premium, if any, and
               accrued interest on the Notes on the Stated Maturity of such
               payments in accordance with the terms of this Indenture and
               the Notes;

                    (B)  the Company has delivered to the Trustee (i)
               either (x) an Opinion of Counsel to the effect that Holders
               will not recognize income, gain or loss for federal income
               tax purposes as a result of the Company's exercise of its
               option under this Section 8.02 and will be subject to
               federal income tax on the same amount and in the same manner
               and at the same times as would have been the case if such
               deposit, defeasance and discharge had not occurred, which
               Opinion of Counsel must be based upon (and accompanied by a
               copy of) a ruling of the Internal Revenue Service to the
               same effect unless there has been a change in applicable
               federal income tax law after the Closing Date such that a
               ruling is no longer required or (y) a ruling directed to the
               Trustee received from the Internal Revenue Service to the
               same effect as the aforementioned Opinion of Counsel and
               (ii) an Opinion of Counsel to the effect that the creation
               of the defeasance trust does not violate the Investment
               Company Act of 1940 and after the passage of 123 days
               following the deposit, the trust fund will not be subject to
               the effect of Section 547 of the United States Bankruptcy
               Code or Section 15 of the New York Debtor and Creditor Law;

                    (C)  immediately after giving effect to such deposit on
               a pro forma basis, no Event of Default, or event that after
               the giving of notice or lapse of time or both would become
               an Event of Default, shall have occurred and be continuing
               on the date of such deposit or during the period ending on
               the 123rd day after the date of such deposit, and such
               deposit shall not result in a breach or violation of, or
               constitute a default under, any other agreement or
               instrument to which the Company or any of its Subsidiaries
               is a party or by which the Company or any of its
               Subsidiaries is bound;

                    (D)  if at such time the Notes are listed on a national
               securities exchange, the Company has delivered to the
               Trustee an Opinion of Counsel to the effect that the Notes
               will not be delisted as a result of such deposit, defeasance
               and discharge, provided that if simultaneously with the 
                              --------
               deposit of the money and/or U.S. Government Obligations
               referred to in (A) above, the Company has caused an
               irrevocable, transferrable, standby letter of credit to be
               issued by a bank with capital and surplus exceeding the
               principal amount of the Notes then outstanding, expiring not
               earlier than 180 days from its issuance, in favor of the
               Trustee which permits the Trustee to draw an amount equal to
               the principal, premium, if any, and accrued interest on the
               Notes through the expiry date of the letter of credit, then
               the Company will be deemed to have paid and discharged any
               and all obligations in respect of the Notes on the date of
               the deposit and issuance of the letter of credit; and

                    (E)  the Company has delivered to the Trustee an
               Officers' Certificate and an Opinion of Counsel, in each
               case stating that all conditions precedent provided for
               herein relating to the defeasance contemplated by this
               Section 8.02 have been complied with.

                    Notwithstanding the foregoing, prior to the end of the
          123-day period referred to in clause (B)(ii) of this Section
          8.02, none of the Company's obligations under this Indenture
          shall be discharged.  Subsequent to the end of such 123-day
          period with respect to this Section 8.02, the Company's
          obligations in Sections 2.02, 2.03, 2.04, 2.05, 2.06, 2.07, 2.08,
          2.09, 2.14, 4.01, 4.02, 7.07, 7.08, 8.05 and 8.06 shall survive
          until the Notes are no longer outstanding.  Thereafter, only the
          Company's obligations in Sections 7.07, 8.05 and 8.06 shall
          survive.  If and when a ruling from the Internal Revenue Service
          or an Opinion of Counsel referred to in clause (B)(i) of this
          Section 8.02 may be provided specifically without regard to, and
          not in reliance upon, the continuance of the Company's
          obligations under Section 4.01, then the Company's obligations
          under such Section 4.01 shall cease upon delivery to the Trustee
          of such ruling or Opinion of Counsel and compliance with the
          other conditions precedent provided for herein relating to the
          defeasance contemplated by this Section 8.02.

                    After any such irrevocable deposit, the Trustee upon
          request shall acknowledge in writing the discharge of the
          Company's obligations under the Notes and this Indenture except
          for those surviving obligations in the immediately preceding
          paragraph.

                    SECTION 8.03.  Defeasance of Certain Obligations.  The
                                   ---------------------------------
          Company may omit to comply with any term, provision or condition
          set forth in clause (iii) of Section 5.01 and Sections 4.03
          through 4.18, and clause (c) of Section 6.01 with respect to
          clause (iii) of Section 5.01 and Sections 4.03 through 4.18, and
          clauses (c), (d), (e), (f) and (g) of Section 6.01 shall be
          deemed not to be Events of Default upon:

                    (a)  the deposit with the Trustee, in trust, of money
               and/or U.S. Government Obligations that through the payment
               of interest and principal in respect thereof in accordance
               with their terms will provide money in an amount sufficient
               to pay the principal of, premium, if any, and accrued
               interest on the Notes on the Stated Maturity of such
               payments in accordance with the terms of this Indenture and
               the Notes;

                    (b)  the satisfaction of the provisions described in
               clauses (B)(ii), (C) and (D) of Section 8.02 hereof;

                    (c)  the delivery by the Company to the Trustee of an
               Opinion of Counsel to the effect that the Holders will not
               recognize income, gain or loss for federal income tax
               purposes as a result of such deposit and defeasance and will
               be subject to federal income tax on the same amount and in
               the same manner and at the same times as would have been the
               case if such deposit and defeasance had not occurred; and

                    (d)  the Company has delivered to the Trustee an
               Officers' Certificate and an Opinion of Counsel, in each
               case stating that all conditions precedent provided for
               herein relating to the defeasance contemplated by this
               Section 8.03 have been complied with.

                    SECTION 8.04.  Application of Trust Money.  Subject to
                                   --------------------------
          Section 8.06, the Trustee or Paying Agent shall hold in trust
          money or U.S. Government Obligations deposited with it pursuant
          to Section 8.01, 8.02 or 8.03, as the case may be, and shall
          apply the deposited money and the money from U.S. Government
          Obligations in accordance with the Notes and this Indenture to
          the payment of principal of, premium, if any, and interest on the
          Notes; but such money need not be segregated from other funds
          except to the extent required by law.

                    SECTION 8.05.  Repayment to Company.  Subject to 
                                   --------------------
          Sections 7.07, 8.01, 8.02 and 8.03, the Trustee and the Paying
          Agent shall promptly pay to the Company upon request set forth in
          an Officers' Certificate any excess money held by them at any
          time and thereupon shall be relieved from all liability with
          respect to such money.  The Trustee and the Paying Agent shall
          pay to the Company upon request any money held by them for the
          payment of principal, premium, if any, or interest that remains
          unclaimed for two years; provided that the Trustee or such Paying
                                   --------
          Agent before being required to make any payment may cause to be
          published at the expense of the Company once in a newspaper of
          general circulation in the City of New York or mail to each
          Holder entitled to such money at such Holder's address (as set
          forth in the Note Register) notice that such money remains
          unclaimed and that after a date specified therein (which shall be
          at least 30 days from the date of such publication or mailing)
          any unclaimed balance of such money then remaining will be repaid
          to the Company.  After payment to the Company, Holders entitled
          to such money must look to the Company for payment as general
          creditors unless an applicable law designates another Person, and
          all liability of the Trustee and such Paying Agent with respect
          to such money shall cease.

                    SECTION 8.06.  Reinstatement.  If the Trustee or Paying
                                   -------------
          Agent is unable to apply any money or U.S. Government Obligations
          in accordance with Section 8.01, 8.02 or 8.03, as the case may
          be, by reason of any legal proceeding or by reason of any order
          or judgment of any court or governmental authority enjoining,
          restraining or otherwise prohibiting such application, the
          Company's obligations under this Indenture and the Notes shall be
          revived and reinstated as though no deposit had occurred pursuant
          to Section 8.01, 8.02 or 8.03, as the case may be, until such
          time as the Trustee or Paying Agent is permitted to apply all
          such money or U.S. Government Obligations in accordance with
          Section 8.01, 8.02 or 8.03, as the case may be; provided that, if
                                                          --------
          the Company has made any payment of principal of, premium, if
          any, or interest on any Notes because of the reinstatement of its
          obligations, the Company shall be subrogated to the rights of the
          Holders of such Notes to receive such payment from the money or
          U.S. Government Obligations held by the Trustee or Paying Agent.

                    SECTION 8.07.  Defeasance and Certain Other Events of 
                                   --------------------------------------
          Default.  In the event the Company exercises its option to omit 
          -------
          compliance with certain covenants and provisions of this
          Indenture with respect to the Notes pursuant to Section 8.03 and
          such Notes are declared due and payable because of the occurrence
          of an Event of Default that remains applicable, the amount of
          money and/or U.S. Government Obligations on deposit with the
          Trustee will be sufficient to pay amounts due on such Notes at
          the time of their Stated Maturity.  If, in the event the Company
          exercises its option to omit compliance with certain covenants
          and provisions of this Indenture with respect to the Notes
          pursuant to Section 8.03 and such Notes are declared due and
          payable because of the occurrence of an Event of Default that
          remains applicable, the amount of money and/or U.S. Government
          Obligations on deposit with the Trustee is insufficient to pay
          amounts due on the Notes at the time of the acceleration
          resulting from such Events of Default pursuant to Section 6.02,
          the Company will remain liable for such payments.


                                     ARTICLE NINE
                         AMENDMENTS, SUPPLEMENTS AND WAIVERS

                    SECTION 9.01.  Without Consent of Holders.  The 
                                   --------------------------
          Company, when authorized by resolutions of its Board of
          Directors, and the Trustee may amend or supplement this Indenture
          or the Notes without notice to, or the consent of, any Holder:

                    (i)  to cure any ambiguity, defect or inconsistency in
               this Indenture; provided that such amendments or supplements
                               --------
               shall not adversely affect the interests of the Holders in
               any material respect;

                    (ii)  to comply with Article Five;

                    (iii) to comply with any requirements of the
               Commission in connection with the qualification of this
               Indenture under the TIA;

                    (iv)  to evidence and provide for the acceptance of
               appointment hereunder by a successor Trustee; or

                    (v)   to make any change that, in the opinion of the
               Board of Directors of the Company evidenced by a Board
               Resolution, does not materially and adversely affect the
               rights of any Holder.

                    SECTION 9.02.  With Consent of Holders.  Subject to 
                                   -----------------------
          Sections 6.04 and 6.07 and without prior notice to the Holders,
          the Company, when authorized by its Board of Directors (as
          evidenced by a Board Resolution), and the Trustee may amend this
          Indenture and the Notes with the written consent of the Holders
          of a majority in aggregate principal amount at maturity of the
          Notes then outstanding, and the Holders of a majority in
          principal amount at maturity of the Notes then outstanding by
          written notice to the Trustee may waive future compliance by the
          Company with any provision of this Indenture or the Notes.

                    Notwithstanding the provisions of this Section 9.02,
          without the consent of each Holder affected thereby, an amendment
          or waiver, including a waiver pursuant to Section 6.04, may not:

                    (i)   change the Stated Maturity of the principal of, or
               any installment of interest on, any Note;

                    (ii)  reduce the Accreted Value or principal amount of,
               or premium, if any, or interest on, any Note;

                    (iii) change the place or currency of payment of
               principal of, or premium, if any, or interest on, any Note;

                    (iv)  impair the right to institute suit for the
               enforcement of any payment on or after the Stated Maturity
               (or, in the case of a redemption, on or after the Redemption
               Date) of any Note;

                    (v)   reduce the above-stated percentage in principal
               amount at maturity of outstanding Notes the consent of whose
               Holders is necessary to modify or amend this Indenture;

                    (vi)  waive a Default in the payment of principal of,
               premium, if any, or interest on, any Note; or

                    (vii) reduce the percentage or aggregate principal
               amount at maturity of outstanding Notes the consent of whose
               Holders is necessary for waiver of compliance with certain
               provisions of the Indenture or for waiver of certain
               defaults.

                    It shall not be necessary for the consent of the
          Holders under this Section 9.02 to approve the particular form of
          any proposed amendment, supplement or waiver, but it shall be
          sufficient if such consent approves the substance thereof.

                    After an amendment, supplement or waiver under this
          Section 9.02 becomes effective, the Company shall mail to the
          Holders affected thereby a notice briefly describing the
          amendment, supplement or waiver.  The Company will mail
          supplemental indentures to Holders upon request.  Any failure of
          the Company to mail such notice, or any defect therein, shall
          not, however, in any way impair or affect the validity of any
          such supplemental indenture or waiver.

                    SECTION 9.03.  Revocation and Effect of Consent.  Until
                                   --------------------------------
          an amendment or waiver becomes effective, a consent to it by a
          Holder is a continuing consent by the Holder and every subsequent
          Holder of a Note or portion of a Note that evidences the same
          debt as the Note of the consenting Holder, even if notation of
          the consent is not made on any Note.  However, any such Holder or
          subsequent Holder may revoke the consent as to its Note or
          portion of its Note.  Such revocation shall be effective only if
          the Trustee receives the notice of revocation before the date the
          amendment, supplement or waiver becomes effective.  An amendment,
          supplement or waiver shall become effective on receipt by the
          Trustee of written consents from the Holders of the requisite
          percentage in principal amount at maturity of the outstanding
          Notes.

                    The Company may, but shall not be obligated to, fix a
          record date for the purpose of determining the Holders entitled
          to consent to any amendment, supplement or waiver.  If a record
          date is fixed, then, notwithstanding the last two sentences of
          the immediately preceding paragraph, those Persons who were
          Holders at such record date (or their duly designated proxies)
          and only those Persons shall be entitled to consent to such
          amendment, supplement or waiver or to revoke any consent
          previously given, whether or not such Persons continue to be
          Holders after such record date.  No such consent shall be valid
          or effective for more than 90 days after such record date.

                    After an amendment, supplement or waiver becomes
          effective, it shall bind every Holder unless it is of the type
          described in any of clauses (i) through (iv) of Section 9.02.  In
          case of an amendment or waiver of the type described in clauses
          (i) through (iv) of Section 9.02, the amendment or waiver shall
          bind each Holder who has consented to it and every subsequent
          Holder of a Note that evidences the same indebtedness as the Note
          of the consenting Holder.

                    SECTION 9.04.  Notation on or Exchange of Notes.  If an
                                   --------------------------------
          amendment, supplement or waiver changes the terms of a Note, the
          Trustee may require the Holder to deliver it to the Trustee.  The
          Trustee may place an appropriate notation on the Note about the
          changed terms and return it to the Holder and the Trustee may
          place an appropriate notation on any Note thereafter
          authenticated.  Alternatively, if the Company or the Trustee so
          determines, the Company in exchange for the Note shall issue and
          the Trustee shall authenticate a new Note that reflects the
          changed terms.

                    SECTION 9.05.  Trustee to Sign Amendments, Etc.  The 
                                   --------------------------------
          Trustee shall be entitled to receive, and shall be fully
          protected in relying upon, an Opinion of Counsel stating that the
          execution of any amendment, supplement or waiver authorized
          pursuant to this Article Nine is authorized or permitted by this
          Indenture.  Subject to the preceding sentence, the Trustee shall
          sign such amendment, supplement or waiver if the same does not
          adversely affect the rights of the Trustee.  The Trustee may, but
          shall not be obligated to, execute any such amendment, supplement
          or waiver that affects the Trustee's own rights, duties or
          immunities under this Indenture or otherwise.

                    SECTION 9.06.  Conformity with Trust Indenture Act.  
                                   -----------------------------------
          Every supplemental indenture executed pursuant to this Article
          Nine shall conform to the requirements of the TIA as then in
          effect.


                                     ARTICLE TEN
                                    MISCELLANEOUS

                    SECTION 10.01.  Trust Indenture Act of 1939.  Prior to
                                    ---------------------------
          the effectiveness of the Registration Statement, this Indenture
          shall incorporate and be governed by the provisions of the TIA
          that are required to be part of and to govern indentures
          qualified under the TIA.  After the effectiveness of the
          Registration Statement, this Indenture shall be subject to the
          provisions of the TIA that are required to be a part of this
          Indenture and shall, to the extent applicable, be governed by
          such provisions.

                    SECTION 10.02.  Notices.  Any notice or communication 
                                    -------
          shall be sufficiently given if in writing and delivered in person
          or mailed by first class mail, commercial courier service or
          telecopier communication, addressed as follows:

                    if to the Company:
                    -----------------

                         ICG Services, Inc.
                         9605 East Maroon Circle
                         P.O. Box 6742
                         Englewood, Colorado  80155-6742
                         Attention:  Chief Financial Officer

                    if to the Trustee:
                    -----------------

                         Norwest Bank Colorado, N.A.
                         1740 Broadway
                         Denver, Colorado  80274-8693
                         Attention:  Corporate Trust and Escrow Services

                    The Company or the Trustee, by notice to the other may
          designate additional or different addresses for subsequent
          notices or communications.

                    Any notice or communication mailed to a Holder shall be
          mailed to him at his address as it appears on the Note Register
          by first class mail and shall be sufficiently given to him if so
          mailed within the time prescribed.  Copies of any such
          communication or notice to a Holder shall also be mailed to the
          Trustee and each Agent at the same time.

                    Failure to mail a notice or communication to a Holder
          or any defect in it shall not affect its sufficiency with respect
          to other Holders.  Except for a notice to the Trustee, which is
          deemed given only when received, and except as otherwise provided
          in this Indenture, if a notice or communication is mailed in the
          manner provided in this Section 10.02, it is duly given, whether
          or not the addressee receives it.

                    Where this Indenture provides for notice in any manner,
          such notice may be waived in writing by the Person entitled to
          receive such notice, either before or after the event, and such
          waiver shall be the equivalent of such notice.  Waivers of notice
          by Holders shall be filed with the Trustee, but such filing shall
          not be a condition precedent to the validity of any action taken
          in reliance upon such waiver.

                    In case by reason of the suspension of regular mail
          service or by reason of any other cause it shall be impracticable
          to give such notice by mail, then such notification as shall be
          made with the approval of the Trustee shall constitute a
          sufficient notification for every purpose hereunder.

                    SECTION 10.03.  Certificate and Opinion As to 
                                    -----------------------------
          Conditions Precedent.  Upon any request or application by the 
          --------------------
          Company to the Trustee to take any action under this Indenture,
          the Company shall furnish to the Trustee:

                    (i)  an Officers' Certificate stating that, in the
               opinion of the signers, all conditions precedent, if any,
               provided for in this Indenture relating to the proposed
               action have been complied with; and

                    (ii) an Opinion of Counsel stating that, in the opinion
               of such Counsel, all such conditions precedent have been
               complied with.

                    SECTION 10.04.  Statements Required in Certificate or 
                                    -------------------------------------
          Opinion.  Each certificate or opinion with respect to compliance
          -------
          with a condition or covenant provided for in this Indenture shall
          include:

                    (i)   a statement that each person signing such
               certificate or opinion has read such covenant or condition
               and the definitions herein relating thereto;

                    (ii)  a brief statement as to the nature and scope of
               the examination or investigation upon which the statement or
               opinion contained in such certificate or opinion is based;

                    (iii) a statement that, in the opinion of each such
               person, he has made such examination or investigation as is
               necessary to enable him to express an informed opinion as to
               whether or not such covenant or condition has been complied
               with; and

                    (iv)  a statement as to whether or not, in the opinion
               of each such person, such condition or covenant has been
               complied with; provided, however, that, with respect to 
                              --------  -------
               matters of fact, an Opinion of Counsel may rely on an
               Officers' Certificate or certificates of public officials.

                    SECTION 10.05.  Rules by Trustee, Paying Agent or 
                                    ---------------------------------
          Registrar.  The Trustee may make reasonable rules for action by 
          ---------
          or at a meeting of Holders.  The Paying Agent or Registrar may
          make reasonable rules for its functions.

                    SECTION 10.06.  Payment Date Other Than a Business Day. 
                                    --------------------------------------
          If an Interest Payment Date, Redemption Date, Payment Date,
          Stated Maturity or date of maturity of any Note shall not be a
          Business Day, then payment of principal of, premium, if any, or
          interest on such Note, as the case may be, need not be made on
          such date, but may be made on the next succeeding Business Day
          with the same force and effect as if made on the Interest Payment
          Date, Payment Date, or Redemption Date, or at the Stated Maturity
          or date of maturity of such Note; provided that no interest shall
                                            --------
          accrue for the period from and after such Interest Payment Date,
          Payment Date, Redemption Date, Stated Maturity or date of
          maturity, as the case may be.

                    SECTION 10.07.  Governing Law; Submission to 
                                    ----------------------------
          Jurisdiction.  This Indenture and the Notes shall be governed by
          ------------
          the laws of the State of New York.  The Company agrees to submit
          to the jurisdiction of any federal or state court located in the
          City of New York in any suit, action or proceeding with respect
          to this Indenture or the Notes and for actions brought under the
          U.S. federal or state securities laws brought in any such court.

                    SECTION 10.08.  No Adverse Interpretation of Other 
                                    ----------------------------------
          Agreements.  This Indenture may not be used to interpret another
          ----------
          indenture, loan or debt agreement of the Company or any
          Subsidiary of the Company.  Any such indenture, loan or debt
          agreement may not be used to interpret this Indenture.

                    SECTION 10.09.  No Recourse Against Others.  No 
                                    --------------------------
          recourse for the payment of the principal of, premium, if any, or
          interest on any of the Notes, or for any claim based thereon or
          otherwise in respect thereof, and no recourse under or upon any
          obligation, covenant or agreement of the Company contained in
          this Indenture, or in any of the Notes, or because of the
          creation of any Indebtedness represented thereby, shall be had
          against any incorporator or against any past, present or future
          partner, shareholder, other equityholder, officer, director,
          employee or controlling person, as such, of the Company or of any
          successor Person, either directly or through the Company or any
          successor Person, whether by virtue of any constitution, statute
          or rule of law, or by the enforcement of any assessment or
          penalty or otherwise; it being expressly understood that all such
          liability is hereby expressly waived and released as a condition
          of, and as a consideration for, the execution of this Indenture
          and the issue of the Notes.

                    SECTION 10.10.  Successors.  All agreements of the 
                                    ----------
          Company in this Indenture and the Notes shall bind its
          successors.  All agreements of the Trustee in this Indenture
          shall bind its successors.

                    SECTION 10.11.  Duplicate Originals.  The parties may 
                                    -------------------
          sign any number of copies of this Indenture.  Each signed copy
          shall be an original, but all of them together represent the same
          agreement.

                    SECTION 10.12.  Separability.  In case any provision in
                                    ------------
          this Indenture or in the Notes shall be invalid, illegal or
          unenforceable, the validity, legality and enforceability of the
          remaining provisions shall not in any way be affected or impaired
          thereby.

                    SECTION 10.13.  Table of Contents, Headings, Etc.  The
                                    ---------------------------------
          Table of Contents, Cross-Reference Table and headings of the
          Articles and Sections of this Indenture have been inserted for
          convenience of reference only, are not to be considered a part
          hereof and shall in no way modify or restrict any of the terms
          and provisions hereof.


          


                                      SIGNATURES

                    IN WITNESS WHEREOF, the parties hereto have caused this
          Indenture to be duly executed, all as of the date first written
          above.


                                           ICG SERVICES, INC.


                                           By: /s/ Don Teague
                                              -------------------------
                                              Name: H. Don Teague
                                              Title: Executive Vice President,
                                                     General Counsel and
                                                     Secretary





                                           NORWEST BANK COLORADO, N.A.
                                              as Trustee


                                           By:/s/ A. Lenore Martinez
                                              -------------------------
                                              Name: A. Lenore Martinez
                                              Title: Sr. Vice President


          


                                                                  EXHIBIT A
                                                                  ---------


                                    [FACE OF NOTE]

                                  ICG SERVICES INC.

                          10% Senior Discount Note Due 2008

                                                  [CUSIP] [CINS]           
                                                                 ----------


          No.                                                    $         
                                                                  ---------

                    The following information is supplied for purposes of
          Sections 1273 and 1275 of the Internal Revenue Code:

          Issue Date:  February 12, 1998

          Yield to maturity for period from Issue Date to February 15,
          2008:  10.00% , compounded semiannually on February 15 and August
          15 commencing February 15, 1998 (computed without giving effect
          to the additional payments of interest in the event the issuer
          fails to commence the exchange offer and fails to cause the shelf
          registration statement to be declared effective, each as referred
          to on the reverse hereof)

          Original issue discount under Section 1273 of the Internal
          Revenue Code (for each $1,000 principal amount at maturity):  
          $886.59

          Issue Price (for each $1,000 principal amount at maturity): 
          $613.41

                    ICG SERVICES, INC., a Delaware corporation (the
          "Company", which term includes any successor under the Indenture
          hereinafter referred to), for value received, promises to pay to
          [            ], or its registered assigns, the principal sum of
           ------------
          [     ] ($[     ]) on [          ], 2008.
           -----     -----       ----------

                    Interest Payment Dates:  February 15 and August 15,
          commencing August 15, 2003.

                    Regular Record Dates:  February 1 and August 1.


          


                    Reference is hereby made to the further provisions of
          this Note set forth on the reverse hereof, which further
          provisions shall for all purposes have the same effect as if set
          forth at this place.

                    IN WITNESS WHEREOF, the Company has caused this Note to
          be signed manually or by facsimile by its duly authorized
          officers.


          Date:  February 12, 1998      ICG SERVICES, INC.


                                        By:
                                           -------------------------------
                                           Name:
                                           Title:

                                        By:
                                           -------------------------------
                                           Name:
                                           Title:


                  (Form of Trustee's Certificate of Authentication)

          This is one of the 10% Senior Discount Notes due 2008 described
          in the within-mentioned Indenture.


                                        NORWEST BANK COLORADO,
                                        NATIONAL ASSOCIATION, as Trustee


                                        By:
                                           -------------------------------
                                                Authorized Signatory


          


                                [REVERSE SIDE OF NOTE]

                                  ICG SERVICES, INC.

                          10% Senior Discount Note due 2008



          1.   Principal and Interest.
               ----------------------

                    The Company will pay the principal of this 10% Senior
          Discount Note due 2008 (the "Note") on February 15, 2008.

                    The Company promises to pay interest on the principal
          amount of this Note on each Interest Payment Date, as set forth
          below, at the rate per annum shown above.

                    Interest will be payable semiannually (to the holders
          of record of the Notes at the close of business on the February 1
          or August 1 immediately preceding the Interest Payment Date) on
          each Interest Payment Date, commencing August 15, 2003; provided
                                                                  --------
          that no interest shall accrue on the principal amount of this
          Note prior to February 15, 2003 and no interest shall be paid on
          this Note prior to August 15, 2003, except as provided in the
          next paragraph.

                    If an exchange offer registered under the Securities
          Act is not consummated, and a shelf registration statement under
          the Securities Act with respect to resales of the Notes is not
          declared effective by the Commission, on or before August 12,
          1998 in accordance with the terms of the Registration Rights
          Agreement dated February 12, 1998 between the Company and Morgan
          Stanley & Co. Incorporated, interest (in addition to the accrual
          of original discount during the period ending February 15, 2003
          and in addition to the interest otherwise due on the Notes after
          such date) will accrue from August 12, 1998, at an annual rate of
          .5% of the Accreted Value on the preceding Semi-Annual Accrual
          Date, payable in cash semiannually, in arrears, on February 15
          and August 15 of each year, commencing February 15, 1999, until
          the exchange offer is consummated or the shelf registration
          statement is declared effective.  The Holder of this Note is
          entitled to the benefits of such Registration Rights Agreement.

                    From and after February 15, 2003, interest on the Notes
          will accrue from the most recent date to which interest has been
          paid or, if no interest has been paid, from February 15, 2003;
          provided that, if there is no existing default in the payment of
          --------
          interest and this Note is authenticated between a Regular Record
          Date referred to on the face hereof and the next succeeding
          Interest Payment Date, interest shall accrue from such Interest
          Payment Date.  Interest will be computed on the basis of a
          360-day year of twelve 30-day months.

                    The Company shall pay interest on overdue principal and
          premium, if any, and interest on overdue installments of
          interest, to the extent lawful, at a rate per annum that is 2% in
          excess of the rate otherwise payable.

          2.   Method of Payment.
               -----------------

                    The Company will pay principal as provided above and
          interest (except defaulted interest) on the principal amount of
          the Notes as provided above on each February 15 and August 15 to
          the Persons who are Holders (as reflected in the Note Register at
          the close of business on such February 1 and August 1 immediately
          preceding the Interest Payment Date), in each case, even if the
          Note is cancelled on registration of transfer or registration of
          exchange after such record date; provided that, with respect to 
                                           --------
          the payment of principal, the Company will not make payment to
          the Holder unless this Note is surrendered to a Paying Agent.

                    The Company will pay principal, premium, if any, and as
          provided above, interest in money of the United States that at
          the time of payment is legal tender for payment of public and
          private debts.  However, the Company may pay principal, premium,
          if any, and interest by its check payable in such money.  It may
          mail an interest check to a Holder's registered address (as
          reflected in the Note Register).  If a payment date is a date
          other than a Business Day at a place of payment, payment may be
          made at that place on the next succeeding day that is a Business
          Day and no interest shall accrue for the intervening period.

          3.   Paying Agent and Registrar.
               --------------------------

                    Initially, the Trustee will act as authenticating
          agent, Paying Agent and Registrar.  The Company may change any
          authenticating agent, Paying Agent or Registrar without notice. 
          The Company, any Subsidiary or any Affiliate of any of them may
          act as Paying Agent, Registrar or co-Registrar.

          4.   Indenture; Issuance of Additional Notes.
               ---------------------------------------

                    The Company issued the Notes under an Indenture dated
          as of February 12, 1998 (the "Indenture"), between the Company
          and Norwest Bank Colorado, N.A., as trustee (the "Trustee"). 
          Capitalized terms herein are used as defined in the Indenture
          unless otherwise indicated.  The terms of the Notes include those
          stated in the Indenture and those made part of the Indenture by
          reference to the Trust Indenture Act.  The Notes are subject to
          all such terms, and Holders are referred to the Indenture and the
          Trust Indenture Act for a statement of all such terms.  To the
          extent permitted by applicable law, in the event of any
          inconsistency between the terms of this Note and the terms of the
          Indenture, the terms of the Indenture shall control.

                    The Notes are general unsecured obligations of the
          Company.  The Company may, subject to Article Four of the
          Indenture, issue additional Notes under the Indenture.

          5.   Redemption.
               ----------

                    The Notes will be redeemable, at the Company's option,
          in whole or in part, at any time or from time to time, on or
          after February 15, 2003 and prior to maturity, upon not less than
          30 nor more than 60 days' prior notice mailed by first class mail
          to each Holder's last address as it appears in the Note Register,
          at the following Redemption Prices (expressed in percentages of
          their principal amount at maturity), plus accrued and unpaid
          interest, if any, to the Redemption Date (subject to the right of
          Holders of record on the relevant Regular Record Date that is on
          or prior to the Redemption Date to receive interest due on an
          Interest Payment Date), if redeemed during the 12-month period
          commencing February 15, of the years set forth below:

                      Year                     Redemption Price
                      ----                     ----------------
                      2003  . . . . . . . . .    105.0000%
                      2004  . . . . . . . . .    103.3333 
                      2005  . . . . . . . . .    101.6667 

                      2006 and thereafter . .    100.0000 

                    In addition, at any time or from time to time, on or
          prior to February 15, 2001, the Company may, at its option,
          redeem Notes having an aggregate principal amount at maturity of
          up to 35% of the aggregate principal amount at maturity of the
          Notes with the proceeds of one or more public or private Equity
          Offerings, at a Redemption Price equal to   110.0% of the
          Accreted Value thereof on the Redemption Date; provided that at
          least 65% of the aggregate principal amount of Notes initially
          issued remains outstanding after each such redemption.

          6.   Notice of Redemption.
               --------------------

                    Notice of any optional redemption will be mailed at
          least 30 days but not more than 60 days before the Redemption
          Date to each Holder of Notes to be redeemed at his last address
          as it appears in the Note Register.  Notes in original
          denominations larger than $1,000 of principal amount at maturity
          may be redeemed in part.  On and after the Redemption Date,
          interest ceases to accrue on Notes or portions of Notes called
          for redemption, unless the Company defaults in the payment of the
          Redemption Price.

          7.   Repurchase upon Change in Control.
               ---------------------------------

                    Upon the occurrence of any Change of Control, each
          Holder shall have the right to require the repurchase of its
          Notes by the Company in cash pursuant to the offer described in
          the Indenture at a purchase price equal to 101% of the Accreted
          Value thereof plus accrued and unpaid interest, if any, to the
          date of purchase (the "Change of Control Payment").

                    A notice of such Change of Control will be mailed
          within 30 days after any Change of Control occurs to each Holder
          at his last address as it appears in the Note Register.  Notes in
          original denominations larger than $1,000 of principal amount at
          maturity may be sold to the Company in part.  On and after the
          date of the Change of Control Payment, interest ceases to accrue
          on Notes or portions of Notes surrendered for purchase by the
          Company, unless the Company defaults in the payment of the Change
          of Control Payment.

          8.   Denominations; Transfer; Exchange.
               ---------------------------------

                    The Notes are in registered form without coupons in
          denominations of $1,000 of principal amount at maturity and
          multiples of $1,000 in excess thereof.  A Holder may register the
          transfer or exchange of Notes in accordance with the Indenture. 
          The Registrar may require a Holder, among other things, to
          furnish appropriate endorsements and transfer documents and to
          pay any taxes and fees required by law or permitted by the
          Indenture.  The Registrar need not register the transfer or
          exchange of any Notes selected for redemption.  Also, it need not
          register the transfer or exchange of any Notes for a period of 15
          days before a selection of Notes to be redeemed is made.

          9.   Persons Deemed Owners.
               ---------------------

                    A Holder shall be treated as the owner of a Note for
          all purposes.

          10.  Unclaimed Money.
               ---------------

                    If money for the payment of principal, premium, if any,
          or interest remains unclaimed for two years, the Trustee and the
          Paying Agent will pay the money back to the Company at its
          request.  After that, Holders entitled to the money must look to
          the Company for payment, unless an abandoned property law
          designates another Person, and all liability of the Trustee and
          such Paying Agent with respect to such money shall cease.

          11.  Discharge Prior to Redemption or Maturity.
               -----------------------------------------

                    If the Company deposits with the Trustee money and/or
          U.S. Government Obligations sufficient to pay the then
          outstanding principal of, premium, if any, and accrued interest
          on the Notes (a) to redemption or maturity, the Company will be
          discharged from the Indenture and the Notes, except in certain
          circumstances for certain sections thereof, and (b) or to Stated
          Maturity, the Company will be discharged from certain covenants
          set forth in the Indenture.

          12.  Amendment; Supplement; Waiver.
               -----------------------------

                    Subject to certain exceptions, the Indenture or the
          Notes may be amended or supplemented with the consent of the
          Holders of at least a majority in principal amount at maturity of
          the Notes then outstanding, and any existing default or
          compliance with any provision may be waived with the consent of
          the Holders of at least a majority in principal amount at
          maturity of the Notes then outstanding.  Without notice to or the
          consent of any Holder, the parties thereto may amend or
          supplement the Indenture or the Notes to, among other things,
          cure any ambiguity, defect or inconsistency and make any change
          that does not materially and adversely affect the rights of any
          Holder.

          13.  Restrictive Covenants.
               ---------------------

                    The Indenture imposes certain limitations on the
          ability of the Company and its Restricted Subsidiaries, among
          other things, to Incur Indebtedness, make Restricted Payments,
          use the proceeds from Asset Sales, engage in transactions with
          Affiliates or, with respect to the Company, merge, consolidate or
          transfer substantially all of its assets.  Within 90 days after
          the end of the last fiscal quarter of each year, the Company must
          report to the Trustee on compliance with the terms of the
          Indenture.

          14.  Successor Persons.
               -----------------

                    When a successor Person or other entity assumes all the
          obligations of its predecessor under the Notes and the Indenture,
          the predecessor Person will be released from those obligations.

          15.  Defaults and Remedies.
               ---------------------

                    The following events constitute "Events of Default"
          under the Indenture:  (a) default in the payment of principal of
          (or premium, if any, on) any Note when the same becomes due and
          payable at maturity, upon acceleration, redemption or otherwise;
          (b) default in the payment of interest on any Note when the same
          becomes due and payable, and such default continues for a period
          of 30 days; (c) the Company defaults in the performance of or
          breaches any other covenant or agreement of the Company in the
          Indenture or under the Notes (other than a default specified in
          clause (a) or (b) above) and such default or breach continues for
          a period of 30 consecutive days after written notice by the
          Trustee or the Holders of 25% or more in aggregate principal
          amount of the Notes; (d) the Company fails to make or consummate
          an Offer to Purchase in accordance with Section 4.11 of the
          Indenture; (e) the Company fails to make or consummate an Offer
          to Purchase in accordance with Section 4.12 of the Indenture; (f)
          there occurs with respect to any issue or issues of Indebtedness
          of the Company or any Significant Subsidiary having an
          outstanding principal amount of $10 million or more in the
          aggregate for all such issues of all such Persons, whether such
          Indebtedness now exists or shall hereafter be created, (I) an
          event of default that has caused the holder thereof to declare
          such Indebtedness to be due and payable prior to its Stated
          Maturity and such Indebtedness has not been discharged in full or
          such acceleration has not been rescinded or annulled within 30
          days of such acceleration and/or (II) the failure to make a
          principal payment at the final (but not any interim) fixed
          maturity and such defaulted payment shall not have been made,
          waived or extended within 30 days of such payment default; (g)
          any final judgment or order (not covered by insurance) for the
          payment of money in excess of $10 million in the aggregate
          (treating any deductibles, self-insurance or retention as not so
          covered) shall be rendered against the Company or any Significant
          Subsidiary and shall not be paid or discharged, and there shall
          be any period of 30 consecutive days following entry of the final
          judgment or order that causes the aggregate amount for all such
          final judgments or orders outstanding and not paid or discharged
          against the Company or any of its Significant Subsidiaries to
          exceed $10 million during which a stay of enforcement of such
          final judgment or order, by reason of a pending appeal or
          otherwise, shall not be in effect; (h) a court having
          jurisdiction in the premises enters a decree or order for (A)
          relief in respect of the Company or any Significant Subsidiary in
          an involuntary case under any applicable bankruptcy, insolvency
          or other similar law now or hereafter in effect, (B) appointment
          of a receiver, liquidator, assignee, custodian, trustee,
          sequestrator or similar official of the Company or any
          Significant Subsidiary or for all or substantially all of the
          property and assets of the Company or any Significant Subsidiary
          or (C) the winding up or liquidation of the affairs of the
          Company or any Significant Subsidiary and, in each case, such
          decree or order shall remain unstayed and in effect for a period
          of 30 consecutive days; or (i) the Company or any Significant
          Subsidiary (A) commences a voluntary case under any applicable
          bankruptcy, insolvency or other similar law now or hereafter in
          effect, or consents to the entry of an order for relief in an
          involuntary case under any such law, (B) consents to the
          appointment of or taking possession by a receiver, liquidator,
          assignee, custodian, trustee, sequestrator or similar official of
          the Company or any Significant Subsidiary or for all or
          substantially all of the property and assets of the Company or
          any Significant Subsidiary or (C) effects any general assignment
          for the benefit of creditors.

                    If an Event of Default (other than an Event of Default
          specified in clause (h) or (i) above that occurs with respect to
          the Company) occurs and is continuing under the Indenture, the
          Trustee or the Holders of at least 25% in aggregate principal
          amount at maturity of the Notes, then outstanding, by written
          notice to the Company (and to the Trustee if such notice is given
          by the Holders), may, and the Trustee at the request of such
          Holders shall, declare the Accreted Value of, premium, if any,
          and accrued interest, if any, on the Notes to be immediately due
          and payable.

                    If an Event of Default occurs and is continuing, the
          Trustee or the Holders of at least 25% in aggregate principal
          amount at maturity of the Notes then outstanding may declare all
          the Notes to be due and payable.  If a bankruptcy or insolvency
          default with respect to the Company or any Restricted Subsidiary
          occurs and is continuing, the Notes automatically become due and
          payable.  Holders may not enforce the Indenture or the Notes
          except as provided in the Indenture.  The Trustee may require
          indemnity satisfactory to it before it enforces the Indenture or
          the Notes.  Subject to certain limitations, Holders of at least a
          majority in principal amount at maturity of the Notes then
          outstanding may direct the Trustee in its exercise of any trust
          or power.

          16.  Trustee Dealings with Company.
               -----------------------------

                    The Trustee under the Indenture, in its individual or
          any other capacity, may make loans to, accept deposits from and
          perform services for the Company or its Affiliates and may
          otherwise deal with the Company or its Affiliates as if it were
          not the Trustee.

          17.  No Recourse Against Others.
               --------------------------

                    No incorporator or any past, present or future partner,
          stockholder, other equity holder, officer, director, employee or
          controlling person as such, of the Company or of any successor
          Person shall have any liability for any obligations of the
          Company under the Notes or the Indenture or for any claim based
          on, in respect of or by reason of, such obligations or their
          creation.  Each Holder by accepting a Note waives and releases
          all such liability.  The waiver and release are part of the
          consideration for the issuance of the Notes.

          18.  Authentication.
               --------------

                    This Note shall not be valid until the Trustee or
          authenticating agent signs the certificate of authentication on
          the other side of this Note.

          19.  Abbreviations.
               -------------

                    Customary abbreviations may be used in the name of a
          Holder or an assignee, such as:  TEN COM (= tenants in common),
          TEN ENT (= tenants by the entireties), JT TEN (= joint tenants
          with right of survivorship and not as tenants in common), CUST
          (= Custodian) and U/G/M/A (= Uniform Gifts to Minors Act).

               THIS NOTE SHALL BE GOVERNED BY THE LAWS OF THE STATE OF NEW
          YORK.

                    The Company will furnish to any Holder upon written
          request and without charge a copy of the Indenture.  Requests may
          be made to ICG Services, Inc., 9605 East Maroon Circle, P.O. Box
          6742, Englewood, Colorado, 80155-6742, Attention:  Chief
          Financial Officer.


          


                              [FORM OF TRANSFER NOTICE]


                    FOR VALUE RECEIVED the undersigned registered holder
          hereby sell(s), assign(s) and transfer(s) unto

          Insert Taxpayer Identification No.
          ---------------------------------

          -----------------------------------------------------------------
          Please print or typewrite name and address including zip code of
          assignee 
                   --------------------------------------------------------
          the within Note and all rights thereunder, hereby irrevocably
          constituting and appointing 
                                      -------------------------------------
          attorney to transfer said Note on the books of the Company with
          full power of substitution in the premises.


                       [THE FOLLOWING PROVISION TO BE INCLUDED
                       ON ALL NOTES OTHER THAN EXCHANGE NOTES,
                         UNLEGENDED OFFSHORE GLOBAL NOTES AND
                       UNLEGENDED OFFSHORE CERTIFICATED NOTES]

               In connection with any transfer of this Note occurring prior
          to the date which is the earlier of (i) the date of an effective
          Registration or (ii) the end of the period referred to in Rule
          144(k) under the Securities Act, the undersigned confirms that
          without utilizing any general solicitation or general advertising
          that:

                                     [Check One]
                                      ---------

          [  ] (a)  this Note is being transferred in compliance with the
                    exemption from registration under the Securities Act of
                    1933, as amended, provided by Rule 144A thereunder.

                                          or
                                          --

          [  ] (b)  this Note is being transferred other than in accordance
                    with (a) above and documents are being furnished which
                    comply with the conditions of transfer set forth in
                    this Note and the Indenture.

          If none of the foregoing boxes is checked, the Trustee or other
          Registrar shall not be obligated to register this Note in the
          name of any Person other than the Holder hereof unless and until
          the conditions to any such transfer of registration set forth
          herein and in Section 2.08 of the Indenture shall have been
          satisfied.

          Date:
               -----------------   ----------------------------------------
                                   NOTICE:  The signature to this
                                   assignment must correspond with the name
                                   as written upon the face of the within-
                                   mentioned instrument in every
                                   particular, without alteration or any
                                   change whatsoever.



          TO BE COMPLETED BY PURCHASER IF (a) ABOVE IS CHECKED.

               The undersigned represents and warrants that it is
          purchasing this Note for its own account or an account with
          respect to which it exercises sole investment discretion and that
          it and any such account is a "qualified institutional buyer"
          within the meaning of Rule 144A under the Securities Act of 1933,
          as amended, and is aware that the sale to it is being made in
          reliance on Rule 144A and acknowledges that it has received such
          information regarding the Company as the undersigned has
          requested pursuant to Rule 144A or has determined not to request
          such information and that it is aware that the transferor is
          relying upon the undersigned's foregoing representations in order
          to claim the exemption from registration provided by Rule 144A.

          Dated:
                ---------------------   -----------------------------------
                                        NOTICE:  To be executed by an
                                        executive officer


          


                          OPTION OF HOLDER TO ELECT PURCHASE


                    If you wish to have this Note purchased by the Company
          pursuant to Section 4.11 or Section 4.12 of the Indenture, check
          the Box:  [  ]

                    If you wish to have a portion of this Note purchased by
          the Company pursuant to Section 4.11 or Section 4.12 of the
          Indenture, state the amount (in principal amount at maturity):
          $                   .
           -------------------

          Date:
               ---------------

          Your Signature:
                          -------------------------------------------------
                                (Sign exactly as your name appears on
                                      the other side of this Note)

          Signature Guarantee:
                                ----------------------------------


          


                                                                  Exhibit B
                                                                  ---------


                                 Form of Certificate
                                 -------------------



          Norwest Bank Colorado, N.A.                                , 19  
          1740 Broadway                                ----------- --    --
          Denver, Colorado 80274-8693
          Attention:  Corporate Trust and Escrow Services

                    Re:  ICG Services, Inc. (the "Company")
                         10% Senior Discount Notes due 2008 (the "Notes")
                         ------------------------------------------------

          Ladies and Gentlemen:

                    This letter relates to U.S. $                principal
                                                 ---------------
          amount at maturity of Notes represented by a Note (the "Legended
          Note") which bears a legend outlining restrictions upon transfer
          of such Legended Note.  Pursuant to Section 2.02 of the Indenture
          (the "Indenture") dated as of February 12, 1998 relating to the
          Notes, we hereby certify that we are (or we will hold such Notes
          on behalf of) a person outside the United States to whom the
          Notes could be transferred in accordance with Rule 904 of
          Regulation S promulgated under the U.S. Securities Act of 1933,
          as amended.  Accordingly, you are hereby requested to exchange
          the legended certificate for an unlegended certificate
          representing an identical principal amount at maturity of Notes,
          all in the manner provided for in the Indenture.

                    You and the Company are entitled to rely upon this
          letter and are irrevocably authorized to produce this letter or a
          copy hereof to any interested party in any administrative or
          legal proceedings or official inquiry with respect to the matters
          covered hereby.  Terms used in this certificate have the meanings
          set forth in Regulation S.

                                             Very truly yours,

                                             [Name of Holder]



                                             By:
                                                ---------------------------
                                                    Authorized Signature


          


                                                                  Exhibit C
                                                                  ---------



                         Form of Certificate to Be Delivered
                             in Connection with Transfers
                               Pursuant to Regulation S
                         -----------------------------------



          Norwest Bank Colorado, N.A.                                , 19  
          1740 Broadway                                 ---------- --    --
          Denver, Colorado 80274-8693
          Attention:  Corporate Trust and Escrow Services


                    Re:  ICG Services, Inc. (the "Company")
                         10% Senior Discount Notes due 2008 (the "Notes")
                         ------------------------------------------------

          Ladies and Gentlemen:

                    In connection with our proposed sale of U.S.$          
                                                                 ----------
          aggregate principal amount at maturity of the Notes, we confirm
          that such sale has been effected pursuant to and in accordance
          with Regulation S under the Securities Act of 1933, as amended,
          and, accordingly, we represent that:

                    (1)  the offer of the Notes was not made to a person in
          the United States;

                    (2)  at the time the buy order was originated, the
               transferee was outside the United States or we and any
               person acting on our behalf reasonably believed that the
               transferee was outside the United States;

                    (3)  no directed selling efforts have been made by us
               in the United States in contravention of the requirements of
               Rule 903(b) or Rule 904(b) of Regulation S, as applicable;
               and

                    (4)  the transaction is not part of a plan or scheme to
               evade the registration requirements of the U.S. Securities
               Act of 1933.

                    You and the Company are entitled to rely upon this
          letter and are irrevocably authorized to produce this letter or a
          copy hereof to any interested party in any administrative or
          legal proceedings or official inquiry with respect to the matters
          covered hereby.  Terms used in this certificate have the meanings
          set forth in Regulation S.

                                   Very truly yours,

                                   [Name of Transferor]


                                   By:
                                      -------------------------------------
                                               Authorized Signature


          


                                                                  Exhibit D
                                                                  ---------


                              Form of Certificate to Be
                             Delivered in Connection with
                      Transfers to Non-QIB Accredited Investors
                      -----------------------------------------

                                                                           


          Norwest Bank Colorado, N.A.                                , 19  
          1740 Broadway                                  ------------    --
          Denver, Colorado 80274-8693
          Attention:  Corporate Trust and Escrow Services

                    Re:  ICG Services, Inc. (the "Company")
                         10% Senior Discount Notes due 2008 (the "Notes")
                         ------------------------------------------------

          Dear Sirs:

                    In connection with our proposed purchase of
          $            aggregate principal amount of the Notes, we confirm  
           -----------
          that:

                    1.   We understand that any subsequent transfer of the
               Notes is subject to certain restrictions and conditions set
               forth in the Indenture dated as of February 12, 1998
               relating to the Notes (the "Indenture") and the undersigned
               agrees to be bound by, and not to resell, pledge or
               otherwise transfer the Notes except in compliance with, such
               restrictions and conditions and the Securities Act of 1933,
               as amended (the "Securities Act").

                    2.   We understand that the offer and sale of the Notes
               have not been registered under the Securities Act, and that
               the Notes may not be offered or sold except as permitted in
               the following sentence.  We agree, on our own behalf and on
               behalf of any accounts for which we are acting as
               hereinafter stated, that if we should sell any Notes, we
               will do so only (A) to the Company or any subsidiary
               thereof, (B) in accordance with Rule 144A under the
               Securities Act to a "qualified institutional buyer" (as
               defined therein), (C) to an institutional "accredited
               investor" (as defined below) that, prior to such transfer,
               furnishes (or has furnished on its behalf by a U.S. broker-
               dealer) to you and to the Company a signed letter
               substantially in the form of this letter, (D) outside the
               United States in accordance with Rule 904 of Regulation S
               under the Securities Act, (E) pursuant to the provisions of
               Rule 144 under the Securities Act, or (F) pursuant to an
               effective registration statement under the Securities Act,
               and we further agree to provide to any person purchasing any
               of the Notes from us a notice advising such purchaser that
               resales of the Notes are restricted as stated herein.

                    3.   We understand that, on any proposed resale of any
               Notes, we will be required to furnish to you and the Company
               such certifications, legal opinions and other information as
               you and the Company may reasonably require to confirm that
               the proposed sale complies with the foregoing restrictions. 
               We further understand that the Notes purchased by us will
               bear a legend to the foregoing effect.

                    4.   We are an institutional "accredited investor" (as
               defined in Rule 501(a)(1), (2), (3) or (7) of Regulation D
               under the Securities Act) and have such knowledge and
               experience in financial and business matters as to be
               capable of evaluating the merits and risks of our investment
               in the Notes, and we and any accounts for which we are
               acting are each able to bear the economic risk of our or its
               investment.

                    5.   We are acquiring the Notes purchased by us for our
               own account or for one or more accounts (each of which is an
               institutional "accredited investor") as to each of which we
               exercise sole investment discretion.

                    You and the Company are entitled to rely upon this
          letter and are irrevocably authorized to produce this letter or a
          copy hereof to any interested party in any administrative or
          legal proceedings or official inquiry with respect to the matters
          covered hereby.

                                             Very truly yours,

                                             [Name of Transferee]


                                             By:
                                                ---------------------------
                                                    Authorized Signature