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                   FIRST AMENDMENT TO RESTRUCTURING AGREEMENT

                          effective as of May 22, 2002

                                  by and among

                            HY I INVESTMENTS, L.L.C.,

                     THOSE INVESTMENT FUNDS THAT ARE MANAGED
                      BY BENNETT MANAGEMENT CORPORATION AND
            ITS AFFILIATED ENTITIES AND THAT ARE HOLDERS OF OLD NOTES

                                       and

                                 PENTACON, INC.


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         This FIRST AMENDMENT TO RESTRUCTURING AGREEMENT effective as of May 22,
2002 ("this AGREEMENT") is made and entered into by and among HY I INVESTMENTS,
L.L.C., THOSE INVESTMENT FUNDS MANAGED BY BENNETT MANAGEMENT CORPORATION AND ITS
AFFILIATED ENTITIES AND THAT HOLD OLD NOTES (together, the "HOLDERS") and
PENTACON, INC., a Delaware corporation (the "COMPANY"). Capitalized terms not
otherwise defined herein shall have the meaning ascribed to them in the
Restructuring Agreement.

         WHEREAS, the Holders and the Company executed that certain
Restructuring Agreement dated as of April 30, 2002 (the "Restructuring
Agreement") which provided for, among other things, an offer to acquire Old
Notes in exchange for new notes and preferred stock (the "Offer").

         WHEREAS, under the Restructuring Agreement, the Offer was to be
implemented pursuant to an exchange offer or pursuant to a pre-negotiated plan
of reorganization in a case filed under chapter 11 of Title 11 of the United
States Code (the "Bankruptcy Code").

         WHEREAS, pursuant to section 1.02 of the Restructuring Agreement, the
Company and the Holders have the right to consent to or vote for a Superior
Offer.

         WHEREAS, the Board of Directors of the Company and the Holders have
consulted with each other in good faith and have determined that an offer
received by the Company for the purchase of substantially all of its assets of
the Company and its subsidiaries by Anixter International, Inc. (the
"Purchaser") pursuant to a chapter 11 plan is a Superior Offer (the "Purchase
Offer").

         WHEREAS, the Company and Holders desire to amend the Restructuring
Agreement to provide for certain representations, warranties and agreements in
connection with consummating the Purchase Offer pursuant to a chapter 11 plan
and also to prescribe various conditions to the consummation of such
transactions.

         NOW, THEREFORE, in consideration of the mutual covenants and agreements
set forth in this Agreement, and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the parties hereto
agree to amend the Restructuring Agreement as follows:


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                                    ARTICLE I

                                 THE AMENDMENTS

         The Restructuring Agreement is hereby amended as follows (unless
specified otherwise, "Section" and "Article" references used herein refer to
those provisions of the Restructuring Agreement):

SECTION 1.1  Section 1.01 (and all subparts thereof) of the Restructuring
Agreement is hereby amended and restated to read in its entirety as follows:

         Section 1.01  The Plan. Subject to the other terms hereof and
provided that this Agreement shall not have been terminated in accordance
with Section 6.01 and after consultation with the Holders, the Company has
determined to consummate the Purchase Offer by means of a pre-negotiated
chapter 11 plan of reorganization filed under Chapter 11 of the Bankruptcy
Code which incorporates the terms and conditions of the Term Sheet for Joint
Plan of Reorganization attached hereto as Exhibit A (the "Term Sheet"). The
Company, as promptly as practicable after the execution hereof, shall
commence a chapter 11 bankruptcy case and seek confirmation of the Plan by
the Bankruptcy Court. The Company shall consult with the Holders concerning
any amendments or modifications to the Plan and any related disclosure
statement before filing or serving any such amendments in the bankruptcy case.

SECTION 1.2  Section 1.02 (a) of the Restructuring Agreement is amended and
restated to read in its entirety as follows:

         Section 1.02  Holder Actions. (a) subject to the terms and
conditions of this Agreement, each Holder hereby severally:

         (i)      approves and consents to the Term Sheet, including without
                  limitation, the classification and treatment of claims and
                  equity interests described in the Term Sheet;

         (ii)     agrees to vote or cause to be voted all of its Old Notes in
                  favor of a plan of reorganization implementing the Term Sheet
                  and otherwise in form and substance reasonably satisfactory to
                  the Holders (the "Plan") and in connection therewith to
                  execute a ballot or ballots voting to accept the Plan;

         (iii)    agrees to vote against any competing plan that may interfere
                  with or be inconsistent with the Plan and in connection
                  therewith to execute a ballot or ballots voting to reject such
                  competing plan;

         (iv)     agrees not to and will cause its respective officers,
                  directors, employees and professionals or other agents not to,
                  directly or indirectly, take any action to encourage any
                  competing plan that may interfere with or be inconsistent with
                  the Plan, except that nothing herein shall preclude the
                  Holders from soliciting, initiating, or seeking out a Superior
                  Offer; and


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         (v)      agrees to support confirmation of the Plan;

provided, however, that at any time, the Company or the Holders receive a bona
fide offer for the purchase of all or substantially all the assets of the
Company or for the merger or consolidation of the Company with or into any other
company (collectively "Alternative Offer"), which the Board of Directors and the
Holders, in good faith after consultation with each other, determine to be a
superior offer to the Purchase Offer or Plan (a "Superior Offer") then the
Holder shall have the right prior to the confirmation date of the Plan, to
rescind its approval and consent to the Plan and to vote for and consent to such
Superior Offer. Each of the Company and the Holders agree to inform the other
upon its receipt of any proposal, expression of interest or request for
information from any person relating to an Alternative Offer and to deliver to
the other any and all written materials received by such person in connection
therewith. In addition, nothing contained herein shall be deemed to restrict the
sale or transfer by any Holder of any of its Old Notes; provided that the
purchaser thereof shall be bound by the terms of this Agreement, including this
Section 1.02.

SECTION 1.3  Sections 1.03 (a) and (b) of the Restructuring Agreement are
hereby deleted in their entirety.

SECTION 1.4  Section 1.04 of the Restructuring Agreement is amended and
restated to read in its entirety as follows:

         Section 1.04  Conditions to Holders' Obligations. The obligation of
each Holder to undertake the Holder actions required by Section 1.02 is
subject to fulfillment of each of the following conditions (all or any of
which may be waived in whole or in part by such Holder in its sole
discretion):

         (a)      the Plan implementing the Term Sheet and the related
                  disclosure statement shall reflect in all respects the Term
                  Sheet and shall otherwise be in form and substance reasonably
                  satisfactory to the Holders;

         (b)      all debtor-in-possession financing arrangements and related
                  orders shall be in form and substance reasonably satisfactory
                  to the Holders;

         (c)      any amendments or modifications to the Term Sheet or the Plan
                  shall be in form and substance reasonably satisfactory to the
                  Holders;

         (d)      the representations and warranties made by the Company in this
                  Agreement, the Plan and the asset purchase agreement relating
                  to the Purchase Offer (the "Asset Purchase Agreement") shall
                  be true and correct in all material respects on and as of the
                  Confirmation Date as though such representations or warranties
                  were made on and as of such date;

         (e)      the Asset Purchase Agreement shall not have been amended or
                  terminated for any reason; and


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         (f)      not more than 120 days shall have elapsed from the filing of
                  the Chapter 11 case relating to the Plan without the entry of
                  the confirmation order relating thereto.

SECTION 1.5  Article II of the Restructuring Agreement shall be amended to
delete all references to the "Consummation Date" and the "Offer." Section
2.04(b) shall be amended to delete clauses (i) and (ii). Section 2.06(a)
shall be amended to delete any reference to "Offer Documents."

SECTION 1.6  Article III of the Restructuring Agreement shall be amended to
delete all references to "Consummation Date," "Offer" and "Offer Documents."
A new section 3.06 shall be added to Article III as follows:

         Section 3.06  Adequate Disclosure. The information reviewed by and
supplied to Holder with respect to the transaction contemplated under the
Purchase Offer and the Plan has been in all respect sufficient and adequate
to enable Holders to make an informed judgment concerning their support and
approval of the Purchase Offer and the Plan. Holders have been extensively
and adequately involved in the review and negotiation of the Purchase Offer
and the treatment of claims and interests in the Plan. Notwithstanding the
foregoing, this representation shall not constitute a waiver of, nor limit in
any way the Holders' right to require the fulfillment of the conditions
specified in Section 1.04.

SECTION 1.7  Article IV of the Restructuring Agreement is hereby amended to
delete all references to "Consummation Date."

SECTION 1.8  Article V of the Restructuring Agreement is hereby amended to
delete Sections 5.01 and 5.02 in their entirety. Section 5.03 is amended to
delete any reference to "Offer."

SECTION 1.9  Section 6.01 of the Restructuring Agreement is amended and
restated to read in its entirety as follows:

         6.01  Termination. In addition to the other terms and provisions of
this Agreement, this Agreement may be terminated, and the transactions
contemplated hereby may be abandoned:

         (a)      By mutual written agreement of the parties hereto;

         (b)      By either the Company or the Holders upon notification to the
                  non-terminating party by the terminating party:

                  (i)      if the Bankruptcy Court enters an order denying
                           confirmation of the Plan and such order shall have
                           become final and non-appealable;

                  (ii)     upon the election by the Board of Directors and the
                           Holders to pursue or accept an Alternative Offer; or

                  (iii)    in the event the terminating party elects to support
                           an Alternative Offer which it believes is a Superior
                           Offer which is not supported by the non-terminating
                           party.


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         (c)      By the Holders upon notification to the Company prior to the
                  Confirmation Date:

                  (i)      if there has been a breach of any of the
                           representations, warranties, covenants or agreements
                           on the part of the Company set forth in this
                           Agreement;

                  (ii)     if any condition set forth in Section 1.04 of this
                           Agreement is not satisfied as of the date required
                           thereunder, or the Holders reasonably determine that
                           it is not possible for such condition to be satisfied
                           on or prior to such date; or

                  (iii)    if, at any time prior to the Confirmation Date, the
                           Company's senior bank creditors (x) cease to agree to
                           forbear from, or require the payment of any fee in
                           excess of their customary and usual fee for such a
                           forbearance or the modification of any material term
                           of the facility in any way adverse to the Company, in
                           either case, as a condition to their agreeing to
                           continue to forbear from, (1) accelerating the
                           indebtedness owing to them by the Company and/or (2)
                           exercising any of their remedies in respect thereof
                           or (y) take any of the actions described in clauses
                           (1) or (2) immediately above.

SECTION 1.10  Article VII of the Restructuring Agreement is amended to delete
all references to "Offer," and "Consummation Date." Section 7.01 is amended
to delete the reference to Section 5.01.

SECTION 1.11  All Schedules to the Restructuring Agreement are deleted and
the Term Sheet is substituted therefore as Exhibit A to the Restructuring
Agreement.

SECTION 1.12  Capitalized terms used herein and not otherwise defined shall
have the meaning ascribed to such terms in the Restructuring Agreement.

SECTION 1.13  Except as expressly amended by this Agreement, the
Restructuring Agreement is hereby ratified and confirmed in all respects.

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         IN WITNESS WHEREOF, each party hereto has caused this Agreement to be
signed by its officer thereunto duly authorized as of the date first above
written.

                                            HY I INVESTMENTS, L.L.C.


Dated:  ________________                    By:_________________________
                                                 Name:
                                                 Title:

                                            THOSE INVESTMENTS FUNDS THAT ARE
                                            MANAGED BY BENNETT MANAGEMENT
                                            CORPORATION AND ITS AFFILIATED
                                            ENTITIES AND THAT ARE HOLDERS OF
                                            OLD NOTES

                                            By:  BENNETT MANAGEMENT CORPORATION


Dated:  ________________                    By:_________________________
                                                 Name:
                                                 Title:

                                            PENTACON, INC.


Dated:  ________________                    By:_________________________
                                                 Name:
                                                 Title:



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