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                                                                       EXHIBIT 1


                            ILLINOIS TOOL WORKS INC.

                             UNDERWRITING AGREEMENT

                                  $500,000,000
                             5 3/4% Notes due 2009

                                                               February 19, 1999


To the Representatives named in the attached Schedule I
    of the Underwriters named in the attached Schedule II


Ladies and Gentlemen:

     1.   INTRODUCTORY. Illinois Tool Works Inc., a Delaware corporation (the
"Company"), proposes to issue and sell to the underwriters named in Schedule II
(the "Underwriters"), for whom you are acting as representatives (the
"Representatives", which term may refer to a single Representative if so
indicated on Schedule I), the principal amount of its debt securities identified
in Schedule I (the "Securities"), to be issued under an Indenture dated as of
November 1, 1986, as supplemented by a First Supplemental Indenture dated as of
May 1, 1990 (the "Indenture") between the Company and Harris Trust and Savings
Bank, as successor trustee (the "Trustee"). (If the firms listed in Schedule II
include only the firms listed in Schedule I, then the terms "Underwriters" and
"Representatives," as used herein, shall each be deemed to refer to such firms.)

     2.   REPRESENTATIONS  AND  WARRANTIES OF THE COMPANY.  The Company
represents and warrants to each of the Underwriters that:

          (a)  The Company has filed with the Securities and Exchange Commission
     (the "Commission") a registration statement on Form S-3 under the
     Securities Act of 1933, as amended (the "Securities Act") (File No.
     333-70691), for the registration under the Securities Act of the
     Securities. Such registration statement meets the requirements set forth in
     Rule 415(a)(1)(x) under the Securities Act and conforms in all other
     material respects with the applicable rules and regulations of the
     Commission. The Company proposes to file with the Commission pursuant to
     Rule 424(b)(2) or (b)(5) under the Securities Act either (a) a supplement
     to the form of prospectus included in the registration statement relating
     to the Securities and the plan of distribution thereof or (b), if the
     Company elects to rely on Rule 434 under the Securities Act, a Term Sheet
     (as such term is hereinafter defined) relating to the Securities that will
     contain such information as is required or permitted by Rules 434 and
     424(b) under the Securities Act. Such 


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     registration statement has become effective, no stop order suspending its
     effectiveness is in effect and no proceedings for such purpose are pending
     or, to the knowledge of the Company, threatened by the Commission. The
     registration statement, including the exhibits and schedules thereto, is
     hereinafter called the "Registration Statement;" the prospectus in the form
     in which it appears in the Registration Statement is hereinafter called the
     "Basic Prospectus;" and such supplemented form of prospectus, (i) in the
     form in which it is filed with the Commission pursuant to Rule 424(b)(2) or
     (b)(5) (including the Basic Prospectus as so supplemented) or (ii), if the
     Company elects to rely on Rule 434 under the Securities Act, in the form of
     the Term Sheet as first filed with the Commission pursuant to Rule
     424(b)(7) (together with the Basic Prospectus), is hereinafter called the
     "Final Prospectus." Any preliminary form of the Final Prospectus that has
     heretofore been filed pursuant to Rule 424(b) is hereinafter called the
     "Preliminary Final Prospectus." Any abbreviated term sheet that satisfies
     the requirements of Rule 434 under the Securities Act is hereinafter called
     the "Term Sheet." Any reference herein to the Registration Statement, the
     Basic Prospectus, any Preliminary Final Prospectus or the Final Prospectus
     shall be deemed to refer to and include the documents incorporated by
     reference therein pursuant to Item 12 of Form S-3 that were filed under the
     Securities Exchange Act of 1934, as amended (the "Exchange Act"), on or
     before the date of this Agreement, or the issue date of the Basic
     Prospectus, any Preliminary Final Prospectus or the Final Prospectus, as
     the case may be; and any reference herein to the terms "amend," "amendment"
     or "supplement" with respect to the Registration Statement, the Basic
     Prospectus, any Preliminary Final Prospectus or the Final Prospectus shall
     be deemed to refer to and include the filing of any document under the
     Exchange Act after the date of this Agreement, or the issue date of the
     Basic Prospectus, any Preliminary Final Prospectus or the Final Prospectus,
     as the case may be, and deemed to be incorporated therein by reference. As
     used herein, "Incorporated Documents" means the documents that at the time
     are incorporated by reference in the Registration Statement , the Basic
     Prospectus, any Preliminary Final Prospectus or the Final Prospectus.

          (b) When the Final Prospectus is first filed pursuant to Rule 424(b)
     under the Securities Act, when, prior to the Closing Date (as hereinafter
     defined), any amendment to the Registration Statement becomes effective
     (including the filing of any document incorporated by reference in the
     Registration Statement), when any supplement to the Final Prospectus is
     filed with the Commission and at the Closing Date, (i) the Registration
     Statement, as amended as of any such time, the Final Prospectus, as amended
     or supplemented as of any such time, and the Indenture will conform in all
     material respects with the applicable requirements of the Securities Act,
     the Trust Indenture Act of 1939, as amended (the "Trust Indenture Act") and
     the Exchange Act and the respective rules and regulations thereunder and
     (ii) neither the Registration Statement, as amended as of any such time,
     nor the Final Prospectus, as amended or supplemented as of any such time,
     will contain any untrue statement of a material fact or omit to state any
     material fact required to be stated therein or necessary in order to make
     the statements therein not misleading; provided, however, that the Company
     makes no representations or warranties as to (i) that part of the
     Registration Statement that constitutes the Statement


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     of Eligibility (Form T-1) under the Trust Indenture Act of the Trustee,
     (ii) information, if any, contained in the Registration Statement or Final
     Prospectus relating to the Depository Trust Company ("DTC") and its
     book-entry system, or (iii) the information contained in or omitted from
     the Registration Statement or the Final Prospectus or any amendment thereof
     or supplement thereto in reliance upon and in conformity with information
     furnished in writing to the Company by or on behalf of any Underwriter
     through the Representatives specifically for use in connection with the
     preparation of the Registration Statement and the Final Prospectus, it
     being understood that the only such information specifically provided by
     the Underwriters is as described in the penultimate sentence of Section
     7(b).

          (c)  The financial statements, together with the related notes and
     schedules thereto, of the Company and its consolidated subsidiaries
     included in the Registration Statement and the Final Prospectus fairly
     present the financial condition of the Company and its consolidated
     subsidiaries as of the dates indicated and the results of operations and
     cash flows for the periods therein specified; and such financial statements
     have been prepared in accordance with generally accepted accounting
     principles applied on a consistent basis throughout the periods involved,
     except as otherwise stated therein. As used herein, "consolidated
     subsidiaries" means each subsidiary of the Company that is included in the
     consolidated financial statements of the Company contained in its annual
     report to stockholders for 1997 in accordance with the consolidation
     policies set forth therein or which would have been so included if it had
     been a subsidiary of the Company as of the date of such consolidated
     financial statements, and each other subsidiary of the Company which is
     included in consolidated financial statements of the Company prepared from
     time to time thereafter.

          (d)  Subsequent to the respective dates as of which information is
     given in the Registration Statement and the Final Prospectus and prior to
     the Closing Date, except as set forth or contemplated in the Final
     Prospectus, (i) neither the Company nor any of its consolidated
     subsidiaries has entered into any transaction not in the ordinary course of
     business that is material to the Company and its consolidated subsidiaries,
     considered as a whole, (ii) there has been no material adverse change in
     the properties, business, financial condition or results of operations of
     the Company and its consolidated subsidiaries, considered as a whole, and
     (iii) no legal or governmental proceeding that has materially affected the
     Company or any of its consolidated subsidiaries, considered as a whole, or
     the transactions contemplated by this Agreement, has been or will have been
     instituted or threatened.

          (e)  The Company and each of its consolidated subsidiaries has been
     duly incorporated and is validly existing as a corporation in good standing
     under the laws of its jurisdiction of incorporation, with corporate power
     and authority to own or lease its properties and conduct its business as
     currently conducted. The Company each of its consolidated subsidiaries is
     duly qualified as a foreign corporation and is in good standing in each
     jurisdiction in which the nature of its business or its ownership or
     leasing of property requires such qualification, other than those
     jurisdictions as to which the

                                        
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     failure to be so qualified or in good standing would not, individually or
     in the aggregate, reasonably be expected to have a material adverse effect
     on the business, financial condition or results of operations of the
     Company and its consolidated subsidiaries considered as a whole ("Material
     Adverse Effect").

          (f)  The consummation of the transactions herein contemplated and the
     fulfillment of the terms hereof will not result in a breach of any of the
     terms and provisions of, or constitute a default under, (i) the certificate
     of incorporation or by-laws of the Company as presently in effect, (ii) any
     indenture, mortgage, contract or other agreement to which the Company or
     any of its consolidated subsidiaries is a party or is bound, (iii) any
     rule, order statute, law or regulation applicable to the Company or any of
     its consolidated subsidiaries, except, with respect to clause (ii), for
     breaches and defaults that would not, individually or in the aggregate,
     reasonably be expected to have a Material Adverse Effect.

          (g)  The Securities have been duly and validly authorized and, when
     issued, authenticated and delivered against payment therefor in accordance
     with the terms of the Indenture and this Agreement, will constitute valid
     and legally binding obligations of the Company entitled to the benefits of
     the Indenture, except as enforcement thereof may be limited by applicable
     bankruptcy, insolvency, moratorium and other laws affecting the
     enforceability of creditors' rights and general principles of equity, and
     will conform to the description thereof contained in the Final Prospectus.
     The Indenture has been duly authorized, executed and delivered by the
     Company and is a valid and binding agreement, enforceable against the
     Company in accordance with its terms, except as enforcement thereof may be
     limited by applicable bankruptcy, insolvency, moratorium and other laws
     affecting the enforceability of creditors' rights and general principles of
     equity. The Indenture is duly qualified under the Trust Indenture Act and
     conforms to the description thereof contained in the Final Prospectus.

          (h)  No consent, approval, authorization, or order of, or filing with,
     any governmental agency or body or any court is required to be obtained or
     made by the Company for the consummation of the transactions contemplated
     by this Agreement in connection with the sale of the Securities, except
     such as may be required under the Securities Act or under state securities
     or blue sky laws.

          (i)  This Agreement has been duly authorized, validly executed and
     delivered by the Company.

          (j)  The Company and its consolidated subsidiaries possess adequate
     certificates, authorities or permits issued by appropriate governmental
     agencies or bodies necessary to conduct the business now operated by them
     and have not received any notice of proceedings relating to the revocation
     or modification of any such certificates, authorities or permits that, if
     determined adversely to the Company or such subsidiaries, individually or
     in the aggregate, could reasonably be expected to have a Material Adverse
     Effect.


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          (k) Except as disclosed in the Registration Statement and the Final
     Prospectus, neither the Company nor any of its consolidated subsidiaries is
     in violation of any statute, any rule, regulation, decision or order of any
     governmental agency or body or any court, domestic or foreign, relating to
     the use, disposal or release of hazardous or toxic substances or relating
     to the protection or restoration of the environment or human exposure to
     hazardous or toxic substances (collectively, "environmental laws"), owns or
     operates any real property contaminated with any substance that is subject
     to any environmental laws, is liable for any off-site disposal or
     contamination pursuant to any environmental laws, or is subject to any
     claim relating to any environmental laws, which violation, contamination,
     liability or claim, individually or in the aggregate, could reasonably be
     expected to have a Material Adverse Effect.

          (l) Except as disclosed in the Registration Statement and the Final
     Prospectus, there are no pending actions, suits or proceedings against or
     affecting the Company, any of its consolidated subsidiaries or any of their
     respective properties that, if determined adversely to the Company or such
     subsidiaries, individually or in the aggregate, could reasonably be
     expected to have a Material Adverse Effect, or would have a material
     adverse effect on the ability of the Company to perform its obligations
     under this Agreement.

          (m) The Company is not and, after giving effect to the offering and
     sale of the Securities, will not be an "investment company" as defined in
     the Investment Company Act of 1940.

          (n) The Incorporated Documents heretofore filed, when they were filed
     (or, if any amendment with respect to any such document was filed, when
     such amendment was filed), conformed in all material respects with the
     requirements of the Exchange Act and the rules and regulations thereunder,
     any further Incorporated Documents so filed will, when they are filed,
     conform in all material respects with the requirements of the Exchange Act
     and the rules and regulations thereunder; no such document when it was
     filed (or, if an amendment with respect to any such document was filed,
     when such amendment was filed), contained an untrue statement of a material
     fact or omitted to state a material fact required to be stated therein or
     necessary in order to make the untrue statement of a material fact or
     omitted to state a material fact required to be stated therein or necessary
     in order to make the statements therein not misleading; and no such further
     document, when it is filed, will contain an untrue statement of a material
     fact or will omit to state a material fact required to be stated therein or
     necessary in order to make the statements therein not misleading.

          (o) Except as otherwise set forth in the Registration Statement and
     the Final Prospectus, all of the outstanding shares of capital stock of, or
     other ownership interests in, each of the Company's consolidated
     subsidiaries have been duly authorized and validly issued and are fully
     paid and non-assessable and are owned by the Company, free and clear of any
     security interest, claim, lien, encumbrance or adverse interest of any 


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     nature, except for instances that, individually and in the aggregate, could
     not reasonably be expected to have a Material Adverse Effect.

          (p)  Neither the Company nor any of its consolidated subsidiaries is
     in violation of its respective charter or by-laws or in default in the
     performance of any obligation, agreement or condition contained in any
     material bond, debenture, note or any other evidence of material
     indebtedness or in any other agreement, indenture or instrument material to
     the conduct of the business of the Company and its consolidated
     subsidiaries, taken as a whole, to which the Company or any of its
     consolidated subsidiaries is a party or by which it or any of its
     consolidated subsidiaries or their respective property is bound, other than
     violations and defaults that could not reasonably be expected to have a
     Material Adverse Effect.

     3.   SALE, PURCHASE AND DELIVERY OF SECURITIES. On the basis of the
representations and warranties herein contained, but subject to the terms and
conditions herein set forth, the Company agrees to sell to the Underwriters,
severally and not jointly, and each Underwriter, severally and not jointly
(unless otherwise indicated on Schedule I), agrees to purchase from the Company,
at the purchase price set forth in Schedule I, the principal amount of the
Securities set forth opposite such Underwriter's name in Schedule II, except
that, if Schedule I provides for the sale of Securities pursuant to delayed
delivery arrangements, the respective principal amounts of Securities to be
purchased by the Underwriters shall be as set forth in Schedule II, less the
respective amounts of Contract Securities determined as provided below.
Securities to be purchased by the Underwriters are herein sometimes called the
"Underwriters' Securities" and Securities to be purchased pursuant to Delayed
Delivery Contracts as hereinafter provided are herein called "Contract
Securities."

     If so provided in Schedule I, the Underwriters are authorized to solicit
offers to purchase Securities from the Company pursuant to delayed delivery
contracts ("Delayed Delivery Contracts"), substantially in the form of Schedule
III, but with such changes therein as the Company may authorize or approve. The
Underwriters will endeavor to make such arrangements and, as compensation
therefor, the Company will pay to the Representatives, for the account of the
Underwriters, on the Closing Date, the percentage set forth in Schedule I of the
principal amount of the Securities for which Delayed Delivery Contracts are
made. Delayed Delivery Contracts are to be with institutional investors,
including commercial and savings banks, insurance companies, pension funds,
investment companies and educational and charitable institutions. The Company
will make Delayed Delivery Contracts in all cases where sales of Contract
Securities arranged by the Underwriters have been approved by the Company but,
except as the Company may otherwise agree, each such Delayed Delivery Contract
must be for not less than the minimum principal amount set forth in Schedule I
and the aggregate principal amount of Contract Securities may not exceed the
maximum aggregate principal amount set forth in Schedule I. The Underwriters
will not have any responsibility in respect of the validity or performance of
Delayed Delivery Contracts. The principal amount of Securities to be purchased
by each Underwriter as set forth in Schedule II shall be reduced by an amount
which bears the same proportion to the total principal amount of Contract
Securities as the principal amount of Securities set forth opposite the name of
such Underwriter bears to the 


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aggregate principal amount set forth in Schedule II, except to the extent that
you determine that such reduction shall be otherwise than in such proportion and
so advise the Company in writing; provided, however, that the total principal
amount of Securities to be purchased by all Underwriters shall be the aggregate
principal amount set forth in Schedule II, less the aggregate principal amount
of Contract Securities.

     Delivery of and payment for the Underwriters' Securities will be made at
the office, on the date and at the time specified in Schedule I, which date and
time may be postponed by agreement between the Representatives and the Company
or as provided in Section 9 (such date and time of delivery and payment for the
Underwriters' Securities being herein called the "Closing Date"). Delivery of
the Underwriters' Securities shall be made to the Representatives for the
respective accounts of the several Underwriters against payment by the several
Underwriters through the Representatives of the purchase price thereof to or
upon the order of the Company in Federal (same day) funds, or, if so indicated
on Schedule I, in New York Clearinghouse (same day) funds. Certificates for the
Underwriters' Securities shall be registered in such names and in such
denominations as the Representatives may request not less than two full business
days in advance of the Closing Date.

     The Company agrees to have the Underwriters' Securities available for
inspection, checking and packaging by the Representatives in New York, New York,
not later than 1:00 PM on the business day prior to the Closing Date.

     If so provided in Schedule I, Underwriters' Securities will be represented
by one or more definitive global Securities in book-entry form that will be
deposited by or on behalf of the Company with DTC or DTC's designated custodian.
In such case, (a) delivery of the Underwriters' Securities will be made to the
Representatives for the respective accounts of the several Underwriters by
causing DTC to credit the Underwriters' Securities to the account of the
Representatives at DTC, and (b) the Company will cause the certificates
representing the Underwriters' Securities to be made available to the
Representatives for inspection not later than 1:00 p.m., New York City time, on
the business day prior to the Closing Date at the office of DTC or its
designated custodian.

     4.   COVENANTS OF THE COMPANY.  The Company covenants and agrees with the
Underwriters that:

          (a) Prior to the termination of the offering of the Securities, the
     Company will not file any amendment to the Registration Statement or
     supplement (including the Final Prospectus) to the Basic Prospectus unless
     the Company has furnished you a copy for your review prior to filing, and
     the Company will not file any such proposed amendment or supplement to
     which you reasonably object. Subject to the foregoing sentence, the Company
     will cause the Final Prospectus to be timely filed with the Commission
     pursuant to Rule 424 or Rule 434 under the Securities Act. The Company will
     promptly advise the Representatives (i) when the Final Prospectus has been
     filed with the Commission pursuant to Rule 424 or Rule 434 under the
     Securities Act, (ii) when any amendment to the Registration Statement
     relating to the Securities has become effective, 


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     (iii) of any request by the Commission for any amendment of the
     Registration Statement or amendment of or supplement to the Final
     Prospectus or for any additional information, (iv) of the issuance by the
     Commission of any stop order suspending the effectiveness of the
     Registration Statement use of the Final Prospectus or the institution or
     threatening of any proceeding for such purpose and (v) of the receipt by
     the Company of any notification relating to the suspension of the
     qualification of the Securities for sale in any jurisdiction or the
     initiation or threatening of any proceeding for such purpose. The Company
     will use its best efforts to prevent the issuance of any such stop order
     and, if issued, to obtain as soon as possible the withdrawal thereof.

          (b) The Company will prepare and file with the Commission, promptly
     upon the request of the Representatives, any amendments or supplements to
     the Registration Statement or Final Prospectus that, in the opinion of
     counsel for the Underwriters, may be necessary to enable the several
     Underwriters to continue the sale of the Securities, and the Company will
     use its best efforts to cause any such amendments to become effective and
     any such supplements to be filed with the Commission and approved for use
     by the Underwriters as promptly as possible. If at any time when a
     prospectus relating to the Securities is required to be delivered under the
     Securities Act, any event relating to or affecting the Company occurs as a
     result of which the Final Prospectus as then amended or supplemented would
     include an untrue statement of a material fact, or omit to state any
     material fact necessary to make the statement therein not misleading, or if
     it is necessary at any time to amend or supplement the Final Prospectus to
     comply with the Securities Act or the Exchange Act or the respective rules
     thereunder, the Company promptly will prepare and file with the Commission,
     subject to the first sentence of paragraph (a) of this Section 4, an
     amendment or supplement that will correct such statement or omission or
     that will effect such compliance. For purposes of this paragraph (b), the
     Company will furnish such information with respect to itself as the
     Representatives may from time to time reasonably request.

          (c) As soon as practicable, but not later than 90 days after the end
     of the 12-month period beginning at the end of the current fiscal quarter
     of the Company, the Company will make generally available to its security
     holders and you an earnings statement covering a period of at least twelve
     months beginning not earlier than said effective date that shall satisfy
     the provisions of Section 11(a) of the Securities Act.

          (d) The Company will furnish to the Representatives and counsel for
     the Underwriters, without charge, copies of the Registration Statement
     (including exhibits thereto and documents incorporated by reference
     therein) and each amendment thereto that shall become effective on or prior
     to the Closing Date and, so long as delivery of a prospectus by an
     Underwriter or dealer may be required by the Securities Act, as many copies
     of any Preliminary Final Prospectus and the Final Prospectus and any
     amendments thereof and supplements thereto as the Representatives may
     reasonably request. The Company will pay the expenses of printing all
     documents relating to the offering.


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          (e) The Company will furnish such information and execute such
     instruments as may be required to qualify the Securities for sale under the
     securities or blue sky laws of such jurisdictions within the United States
     as you designate, will continue such qualifications in effect so long as
     required for distribution and will arrange for the determination of the
     legality of the Securities for purchase by institutional investors. The
     Company shall not be required to register or qualify as a foreign
     corporation or, except as to matters and transactions relating to the offer
     and sale of the Securities, consent to service of process in any
     jurisdiction.

          (f) The Company will pay all costs and expenses in connection with the
     transactions herein contemplated, including the fees and disbursements of
     its counsel; the fees, costs and expenses of preparing, printing and
     delivering the Indenture and the Securities; the fees, costs and expenses
     of the Trustee; accounting fees and disbursements; the costs and expenses
     in connection with the qualification or exemption of the Securities under
     state securities or blue sky laws, including filing fees and reasonable
     fees and disbursements of counsel for the Underwriters in connection
     therewith and in connection with any Blue Sky Memoranda; the costs and
     expenses in connection with the preparation, printing and filing of the
     Registration Statement (including exhibits thereto) and the Basic,
     Preliminary Final and Final Prospectus, the preparation and copying of this
     Agreement and the furnishing to the Underwriters of such copies of each
     prospectus as the Underwriters may reasonably require; and the fees of
     rating agencies. It is understood, however, that, except as provided in
     this Section and in Sections 7 and 8, the Underwriters will pay all of
     their own costs and expenses, including the fees of their counsel and any
     advertising expenses connected with any offers they may make.

          (g) Until the business day following the Closing Date, the Company
     will not, without the consent of the Representatives, offer or sell, or
     announce the offering of, any debt securities covered by the Registration
     Statement or any other registration statement filed under the Securities
     Act.

     5.   CONDITIONS TO THE OBLIGATIONS OF THE UNDERWRITERS. The obligations of
the several Underwriters to purchase and pay for the Securities are subject to
the condition that the representations and warranties on the part of the Company
contained herein as of the date hereof, as of the date of the effectiveness of
any amendment to the Registration Statement filed prior to the Closing Date
(including the filing of any document incorporated by reference therein) and as
of the Closing Date are true and correct in all material respects, to the
accuracy of the written statements of Company officers made pursuant to the
provisions hereof, to the performance by the Company of its obligations
hereunder to be performed on or prior to the Closing Date and to the following
additional conditions:

          (a) No stop order suspending the effectiveness of the Registration
     Statement, as amended from time to time, shall have been issued and no
     proceedings for that purpose shall have been instituted or shall be
     pending, or, to the knowledge of the Company, shall be contemplated by the
     Commission.


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          (b) No event, nor any material adverse change in the Company's
     business, financial condition or results of operations, shall have
     occurred, nor shall any event exist, that makes untrue or incorrect any
     material statement or information contained in the Registration Statement
     or the Final Prospectus or that is not reflected in the Registration
     Statement or the Final Prospectus, but should be reflected therein in order
     to make the statements or information contained therein not misleading.

          (c) You shall have received at the Closing Date (or prior thereto as
     indicated) the following:

          (i)  An opinion from Stewart S. Hudnut, Senior Vice President, General
          Counsel and Secretary, or an Associate General Counsel of the Company,
          dated the Closing Date, to the effect that:

                    (a) The Company has been duly incorporated and is validly
               existing as a corporation in good standing under the laws of the
               State of Delaware with corporate power and authority to own or
               lease its properties and conduct its business as described in the
               Final Prospectus.

                    (b) Each consolidated subsidiary of the Company (i) that is
               organized under the laws of the United States, any state thereof
               or the District of Columbia and (ii) whose net assets or
               operating revenues exceed 10% of the Company's consolidated net
               assets or consolidated operating revenues, as the case may be, is
               a corporation or other entity validly existing as a corporation
               or other entity in good standing under the laws of its
               jurisdiction of organization with requisite power and authority
               to own or lease its properties and conduct its business as
               presently conducted.

                    (c) The Indenture has been duly authorized, executed and
               delivered by the Company and the Trustee, is duly qualified under
               the Trust Indenture Act, and is a valid and legally binding
               obligation of the Company enforceable in accordance with its
               terms, except as enforcement thereof may be limited by applicable
               bankruptcy, insolvency, moratorium and other laws affecting the
               enforceability of creditors' rights and general principles of
               equity.

                    (d) The Securities have been duly and validly authorized by
               all necessary corporate action, duly executed on behalf of the
               Company, and, when authenticated by the Trustee or the Trustee's
               authenticating agent, and delivered to the several Underwriters
               against payment therefor in accordance with the provisions of
               this Agreement, in the case of the Underwriters' Securities, or
               to the purchasers thereof pursuant to Delayed Delivery Contracts,
               in the case of Contract Securities, will constitute legal, valid
               and binding obligations of the Company enforceable in accordance
               with their terms and entitled to all the benefits of the
               Indenture, except as 


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               enforcement thereof may be limited by applicable bankruptcy,
               insolvency, moratorium and other laws affecting the
               enforceability of creditors' rights and general principles of
               equity.

                    (e) The Indenture and the Securities conform to the
               descriptions thereof in the Final Prospectus, and the statements
               concerning them accurately set forth the provisions thereof
               required to be set forth in the Final Prospectus.

                    (f) This Agreement and any Delayed Delivery Contracts have
               been validly authorized, executed and delivered on behalf of the
               Company.

                    (g) The Registration Statement and any amendments thereto
               have become effective under the Securities Act, and, to the best
               of the knowledge of such counsel, no stop order suspending the
               effectiveness of the Registration Statement, as amended, has been
               issued and no proceedings for that purpose have been instituted
               or are pending or contemplated under the Securities Act, and (1)
               the Registration Statement, the Final Prospectus, and each
               amendment thereof or supplement thereto (except for the financial
               statements and other financial data included therein, as to which
               such counsel need express no opinion) comply as to form in all
               material respects with the requirements of the Securities Act and
               the Exchange Act and the respective rules thereunder; (2) such
               counsel has no reason to believe that, as of its effective date,
               the Registration Statement or any such amendment (except for the
               financial statements and other financial data included therein,
               as to which such counsel need express no opinion) contained an
               untrue statement of a material fact or omitted to state a
               material fact required to be stated therein or necessary to make
               the statements therein not misleading or that the Final
               Prospectus as amended or supplemented as of its issued date
               (except for the financial statements and other financial data
               included therein, as to which such counsel need express no
               opinion) contained an untrue statement of a material fact or
               omitted to state a material fact required to be stated therein or
               necessary to make the statements therein, in light of the
               circumstances under which they were made, not misleading or that,
               as of the Closing Date, either the Registration Statement or the
               Final Prospectus as amended or supplemented (except for the
               financial statements and other financial data included therein,
               as to which such counsel need express no opinion) contains an
               untrue statement of a material fact or omits to state a material
               fact necessary to make the statements therein, in light of the
               circumstances under which they were made, not misleading; (3) the
               descriptions in the Registration Statement and Final Prospectus
               of statutes, legal and governmental proceedings and contracts and
               other documents are accurate and fairly present the information
               required to be shown; and (4) such counsel does not know of any
               legal or governmental proceedings required


                                       11
   12


               to be described in the Final Prospectus that are not described as
               required, or of any contracts or documents of a character
               required to be described in the Registration Statement or Final
               Prospectus or to be filed as exhibits to the Registration
               Statement that are not described and filed as required.

                    (h) The consummation of the transactions herein contemplated
               and the fulfillment of the terms hereof or of any Delayed
               Delivery Contracts will not result in a breach of any of the
               terms and provisions of, or constitute a default under, (i) any
               material indenture, mortgage, deed of trust or other agreement or
               instrument to which, to the knowledge of such counsel, the
               Company or any of its subsidiaries is a party, or (ii) the
               certificate of incorporation or by-laws of the Company as
               presently in effect or, (iii) to the knowledge of such counsel,
               any order, rule or regulation applicable to the Company or any of
               its subsidiaries of any court or of any federal or state
               regulatory body or administrative agency or other governmental
               body having jurisdiction over the Company or any of its
               subsidiaries or their properties.

                    (i) No authorization, approval, consent, order, filing or
               other action of any governmental authority or agency is required
               in connection with the sale of the Securities as contemplated by
               this Agreement or in any Delayed Delivery Contracts except such
               as may be required under the Securities Act or under state
               securities or blue sky laws.

          With respect to the matters set forth in paragraph (g)(2), such
          counsel may state that his belief is based upon his participation in
          the preparation of the Registration Statement and the Final Prospectus
          and any amendments and supplements thereto and upon review and
          discussion of the contents thereof, but, except for the statements in
          the Registration Statement and the Final Prospectus referred to in
          paragraph (g)(3), is without independent check or verification except
          as otherwise specified.

          (ii) An opinion of Gardner, Carton & Douglas, counsel for the Company,
          dated the Closing Date, covering the matters in paragraphs (c),(d),
          (e),(f),(g)(1),(g)(2),(g)(3)(other than as to legal and governmental
          proceedings and contracts and other documents), (h) and (i), provided
          that as to the matters set forth in paragraph (g) (2) of Section 5 (c)
          (i), such counsel may state that their belief is based upon their
          participation in the preparation of the Registration Statement and the
          Final Prospectus and any amendments and supplements thereto (but not
          the documents incorporated by reference therein) and upon review and
          discussion of the contents thereof (including the documents
          incorporated by reference therein), but, except for the statements in
          the Registration Statement and the Final Prospectus referred to in
          paragraph (g)(3) (but only as to statutes), is without independent
          check or verification except as otherwise specified.


                                       12
   13


          (iii) Such opinion or opinions of counsel for the Underwriters, dated
          the Closing Date, as to the sufficiency of all corporate proceedings
          and other legal matters relating to this Agreement, any Delayed
          Delivery Contracts, the validity of the Securities, the Registration
          Statement, the Final Prospectus and other related matters as you may
          reasonably request. The Company shall have furnished to such counsel
          such documents as they may reasonably request for the purpose of
          opinions. In connection with such opinions, such counsel may rely on
          representations or certificates of officers of the Company.

          (iv) A certificate of the President or a Vice President, and the Chief
          Financial Officer of the Company or its Treasurer, dated the Closing
          Date, to the effect that:

                    (a) The representations and warranties of the Company in
               Section 2 of this Agreement are true and correct as of the
               Closing Date, and the Company has complied with all the
               agreements and satisfied all the conditions on its part to be
               performed or satisfied at or prior to the Closing Date.

                    (b) No stop order suspending the effectiveness of the
               Registration Statement has been issued and no proceedings for
               that purpose have been instituted or are pending or, to the
               knowledge of the respective signers of the certificate, are
               contemplated under the Securities Act.

                    (c) The signers of the certificate have carefully examined
               the Registration Statement and the Final Prospectus; neither the
               Registration Statement, the Final Prospectus nor any amendment or
               supplement thereto includes, as of the Closing Date, any untrue
               statement of a material fact or omits, as of the Closing Date, to
               state any material fact required to be stated therein or
               necessary to make the statements therein not misleading; since
               the latest respective dates as of which information is given in
               the Registration Statement, there has been no material adverse
               change in the condition (financial or otherwise), business or
               results of operations of the Company and its consolidated
               subsidiaries, considered as a whole, except as set forth in or
               contemplated by the Final Prospectus; and since the effective
               date of the Registration Statement, as amended, no event has
               occurred which is required to be set forth in the Final
               Prospectus which has not been so set forth.

          (v) Letters from Arthur Andersen LLP, dated the date hereof (and
          delivered prior to the execution and delivery of this Agreement) and
          the Closing Date, addressed to you substantially in the form
          heretofore approved by you.

          (d) Prior to the Closing Date, the Company shall have furnished to you
     such further certificates and documents as you may reasonably request.


                                       13


   14


          (e) The Company shall have accepted Delayed Delivery Contracts in any
     case where sales of Contract Securities arranged by the Underwriters have
     been approved by the Company.

If any condition of the Underwriters' obligations required to be satisfied prior
to the Closing Date is not so satisfied, this Agreement may be terminated by you
by notice in writing or by facsimile transmission to the Company.

In rendering the opinions described in Sections 5(c)(i), (ii) and (iii), counsel
for the Company, and counsel for the Underwriters may, as to matters involving
the laws of any state other than Illinois, rely upon the opinion or opinions of
local counsel satisfactory to you, but in such case a signed copy of each such
opinion shall be furnished to you.

All such opinions (including opinions, if any, of local counsel), certificates,
letters and documents will be in compliance with the provisions hereof only if
they are in all material respects satisfactory to you and to counsel for the
Underwriters, as to which both you and such counsel shall act reasonably. The
Company will furnish you with such conformed copies of such opinions,
certificates, letters and documents as you request.

You, on behalf of the Underwriters, may waive in writing the compliance by the
Company with any one or more of the foregoing conditions or extend the time for
their performance.

     6.   TERMINATION OF AGREEMENT. This Agreement may be terminated by you on
behalf of the Underwriters by notice in writing delivered to the Company prior
to the Closing Date if prior to such time (i) any change, or any development
involving a prospective change in or affecting particularly the business or
properties of the Company and its subsidiaries that, in your reasonable
judgment, materially impairs the investment quality of the Securities, (ii)
trading in the Company's common stock shall have been suspended by the
Commission on the New York Stock Exchange or trading in securities generally on
the New York Stock Exchange shall have been suspended or materially limited, in
either case to such a degree as would in your judgment materially adversely
affect the market for the Securities; (iii) a general moratorium on commercial
banking activities in the State of New York or the United States shall have been
declared by Federal authorities; (iv) any downgrading in the rating of any debt
securities of the Company by any "nationally recognized statistical rating
organization" (as defined for purposes of Rule 436(g) under the Securities Act,
or any public announcement that any such organization has under surveillance or
review its rating of any debt securities of the Company (other than
announcements that have no implication of a possible downgrading), or (v) there
has occurred any material outbreak, or material escalation, of hostilities
involving the United States or other national or international calamity or
crisis, of such magnitude and severity in its effect on the financial markets of
the United States, in your reasonable judgment, as to prevent or materially
impair the marketing, or enforcement of contracts for sale, of the Securities.

If this Agreement is terminated by you because of any failure on the part of the
Company to comply with any of the terms or to fulfill any of the conditions of
this Agreement, or if for any reason the Company is unable to perform its
obligations under this Agreement, the Company


                                       14
                                        
   15


shall pay, in addition to the costs and expenses referred to in Section 4(g),
all reasonable out-of-pocket expenses incurred by the Underwriters in
contemplation of the performance by them of their obligations hereunder,
including the reasonable fees and disbursements of counsel for the Underwriters,
the Underwriters' reasonable printing and travel expenses, and postage and
telephone charges relating directly to the offering contemplated by the Final
Prospectus, and also including advertising expenses incurred after the effective
date of the Registration Statement, it being understood that such out-of-pocket
expenses shall not include any compensation, salaries or wages of the officers,
partners or employees of any of the Underwriters.

The Company shall not in any event be liable to the several Underwriters for
damages on account of loss of anticipated profits arising out of the
transactions contemplated by this Agreement.

     7.   INDEMNIFICATION AND CONTRIBUTION. (a) The Company will indemnify and
hold harmless each Underwriter and each person, if any, who controls any
Underwriter within the meaning of the Securities Act or the Exchange Act against
any losses, claims, damages or liabilities, joint or several, to which such
Underwriter or such controlling person may become subject, under the Securities
Act, the Exchange Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon any
untrue statement or alleged untrue statement of any material fact contained in
the Registration Statement or any amendment thereof, the Basic Prospectus, any
Preliminary Final Prospectus or the Final Prospectus, or any amendment or
supplement thereto, or arise out of or are based upon the omission or alleged
omission to state therein a material fact required to be stated therein or
necessary to make the statements therein not misleading, and will reimburse each
Underwriter and each such controlling person for any legal or other expenses
reasonably incurred by such Underwriter or such controlling person in connection
with investigating or defending any such loss, claim, damage, liability or
action; provided, however, that the Company will not be liable in any such case
to the extent that any such loss, claim, damage or liability arises out of or is
based upon an untrue statement or alleged untrue statement or omission or
alleged omission made therein in reliance upon and in conformity with written
information furnished to the Company by or on behalf of any Underwriter through
the Representatives specifically for use in the preparation thereof; and
provided, further, that the foregoing indemnification with respect to the Basic
Prospectus, any Preliminary Final Prospectus or the Final Prospectus shall not
inure to the benefit of any Underwriter (or any person controlling such
Underwriter) from whom the person asserting any such loss, claim, damage or
liability purchased the Securities, if such Underwriter failed to send or give
copies of the Final Prospectus, as amended or supplemented, excluding documents
incorporated therein by reference, to such person at or prior to the written
confirmation of the sale of such Securities to such person in any case where
such delivery is required by the Securities Act and the untrue statement or
omission of a material fact contained in the Basic Prospectus or any Preliminary
Final Prospectus was corrected in the Final Prospectus (or the Final Prospectus
as amended or supplemented). This indemnity agreement will be in addition to any
liability which the Company may otherwise have.


                                       15
   16



          (b) Each Underwriter severally agrees to indemnify and hold harmless
     the Company, each person, if any, who controls the Company either within
     the meaning of the Securities Act or the Exchange Act, each of its
     directors and each of its officers who has signed the Registration
     Statement, against any losses, claims, damages or liabilities to which the
     Company, any such controlling person or any such director or officer may
     become subject, under the Securities Act, the Exchange Act, or otherwise,
     to the same extent as the foregoing indemnity from the Company to each
     Underwriter, but only with reference to written information relating to
     such Underwriter furnished to the Company by or on behalf of such
     Underwriter through you specifically for use in the preparation of the
     documents referred to in the foregoing indemnity, provided, however, that
     in no case shall any Underwriter be liable or responsible for any amount in
     excess of the underwriting discounts and commissions actually received by
     such Underwriter in connection with the sale of the Securities. This
     indemnity agreement will be in addition to any liability which any
     Underwriter may otherwise have. The Company acknowledges that the
     statements set forth in the last paragraph of the cover page of the Final
     Prospectus and under the heading "Underwriting" or "Plan of Distribution"
     and, if Schedule I provides for sale of Securities pursuant to delayed
     delivery arrangements, in the last sentence under the heading "Delayed
     Delivery Arrangements" in the Final Prospectus constitute the only
     information furnished in writing by or on behalf of the several
     Underwriters for inclusion in the Final Prospectus, and you confirm that
     such statements are correct. This indemnity agreement will be in addition
     to any liability which each such Underwriter may otherwise have.

          (c) Promptly after receipt by an indemnified party under this Section
     of notice of the commencement of any action, such indemnified party will,
     if a claim in respect thereof is to be made against the indemnifying party
     under this Section, notify the indemnifying party in writing of the
     commencement thereof, but the omission so to notify the indemnifying party
     will not relieve it from any liability which it may have to any indemnified
     party otherwise than under this Section. In case any such action is brought
     against any indemnified party, and it notifies the indemnifying party of
     the commencement thereof, the indemnifying party will be entitled to
     participate in and, to the extent that it may elect by written notice
     delivered to the indemnified party promptly after receiving the aforesaid
     notice from such indemnified party, to assume the defense thereof, with
     counsel satisfactory to such indemnified party; provided, however, that if
     the defendants in any such action include both the indemnified party and
     the indemnifying party and the indemnified party shall have reasonably
     concluded that there may be legal defenses available to it and/or other
     indemnified parties which are different from or in addition to those
     available to the indemnifying party, the indemnified party or parties shall
     have the right to select separate counsel to assume such legal defenses and
     to otherwise participate in the defense of such action on behalf of such
     indemnified party or parties. Upon receipt by such indemnified party of
     notice from the indemnifying party of its election so to assume the defense
     of such action and approval by the indemnified party of counsel, the
     indemnifying party will not be liable to such indemnified party under this
     Section 8 for any legal or other expenses subsequently incurred by such
     indemnified party in connection with the defense thereof unless (i) the
     indemnified party shall have 

                                       16
   17



     employed such counsel in connection with the assumption of legal defenses
     in accordance with the proviso to the next preceding sentence (it being
     understood, however, that the indemnifying party shall not be liable for
     the expenses of more than one separate counsel, approved by the
     Representatives of the Underwriters in the case of subparagraph (a),
     representing the indemnified parties under subparagraph (a) or (b), as the
     case may be, who are parties to such action), (ii) the indemnifying party
     shall not have employed counsel satisfactory to the indemnified party to
     represent the indemnified party within a reasonable time after notice of
     commencement of the action or (iii) the indemnifying party has authorized
     the employment of counsel for the indemnified party at the expense of the
     indemnifying party; provided, further, that, with respect to legal and
     other expenses incurred by an indemnified party for which an indemnifying
     party shall be liable hereunder, all such legal fees and expenses shall be
     reimbursed by the indemnifying party as they are incurred.

          (d) In order to provide for just and equitable contribution in
     circumstances in which the indemnification provided for in paragraph (a) of
     this Section 8 is due in accordance with its terms but is for any reason
     held by a court to be unavailable from the Company on grounds of policy or
     otherwise, the Company and the Underwriters shall contribute to the
     aggregate losses, claims, damages and liabilities (including legal or other
     expenses reasonably incurred in connection with investigating or defending
     same) to which the Company and one or more of the Underwriters may be
     subject in such proportion so that the Underwriters are responsible for
     that portion represented by the percentage that the underwriting discount
     bears to the sum of such discount and the purchase price of the Securities
     set forth in Schedule I and the Company is responsible for the balance;
     provided, however, that (i) in no case shall any Underwriter (except as may
     be provided in any agreement among underwriters relating to the offering of
     the Securities) be responsible for any amount in excess of the underwriting
     discount applicable to the Securities purchased by such Underwriter
     hereunder and (ii) no person guilty of fraudulent misrepresentation (within
     the meaning of Section 11(f) of the Securities Act) shall be entitled to
     contribution from any person who was not guilty of such fraudulent
     misrepresentation. For purposes of this Section 8, each person who controls
     an Underwriter within the meaning of the Securities Act shall have the same
     rights to contribution as such Underwriter, and each person who controls
     the Company within the meaning of either the Securities Act or the Exchange
     Act, each officer of the Company who shall have signed the Registration
     Statement and each director of the Company shall have the same rights to
     contribution as the Company, subject in each case to clause (i) of this
     paragraph (d). Any party entitled to contribution will, promptly after
     receipt of notice of commencement of any action, suit or proceeding against
     such party in respect of which a claim for contribution may be made against
     another party or parties under this paragraph (d), notify such party or
     parties from whom contribution may be sought, but the omission to so notify
     such party or parties shall not relieve the party or parties from whom
     contribution may be sought from any other obligation it or they may have
     hereunder or otherwise than under this paragraph (d).


                                       17


   18



     8.   DEFAULT BY AN UNDERWRITER. If the Underwriters' obligations to
purchase Securities pursuant to Section 3 are several and not joint and if any
one or more Underwriters shall fail to purchase and pay for any of the
Securities agreed to be purchased by such Underwriter or Underwriters hereunder
and such failure to purchase shall constitute a default in the performance of
its or their obligations under this Agreement and unless otherwise provided in
Schedule I, the remaining Underwriters shall be obligated severally to take up
and pay for (in the respective proportions which the amount of Securities set
forth opposite their names in Schedule II bear to the aggregate amount of
Securities set opposite the names of all the remaining Underwriters) the
Securities which the defaulting Underwriter or Underwriters agreed but failed to
purchase; provided, however, that in the event that the aggregate amount of
Securities which the defaulting Underwriter or Underwriters agreed but failed to
purchase shall exceed 10% of the aggregate amount of Securities set forth in
Schedule II, the remaining Underwriters shall have the right to purchase all,
but shall not be under any obligation to purchase any, of the Securities, and if
such nondefaulting Underwriters do not purchase all the Securities, this
Agreement will terminate without liability to any nondefaulting Underwriter or
the Company. In the event of a default by any Underwriter as set forth in this
Section 9, the Closing Date shall be postponed for such period, not exceeding
seven days, as the Representatives shall determine in order that the required
changes in the Registration Statement and the Final Prospectus or in any other
documents or arrangements may be effected. Nothing contained in this Agreement
shall relieve any defaulting Underwriter of its liability, if any, to the
Company and any nondefaulting Underwriter for damages occasioned by its default
hereunder.

     9.   REPRESENTATIONS AND INDEMNITIES TO SURVIVE DELIVERY. The respective
indemnities, agreements, representations and warranties of the Company and the
several Underwriters, set forth in or made pursuant to this Agreement, will
remain in full force and effect, regardless of any investigation made by or on
behalf of any Underwriter, the Company or any of its officers or directors or
any controlling person, and will survive delivery of and payment for the
Securities. The provisions of Sections 7 and 8 shall survive the termination or
cancellation of this Agreement.

     10.  NOTICES. All communications hereunder will be in writing and effective
only on receipt, and, if sent to the Representatives, will be mailed, delivered
or sent by facsimile transmission and confirmed to them, at the address
specified in Schedule I ; or, if sent to the Company, will be mailed, delivered
or sent by facsimile transmission and confirmed to the Company at 3600 West Lake
Avenue, Glenview, Illinois 60025-5811, Attention: Treasurer.

     11.  SUCCESSORS; GOVERNING LAW. This Agreement will inure to the benefit of
and be binding upon the parties hereto and the officers and directors and
controlling persons referred to in Section 8 and their respective successors,
assigns, heirs, executors and administrators, and no other persons will have any
right or obligation hereunder. The terms "successors" and "assigns" as used
herein shall not include a purchaser as such from any Underwriter. This
Agreement shall be governed by and construed and enforced in accordance with,
the internal laws of the State of Illinois.


                                       18

   19


     12.  BUSINESS  DAY.  For  purposes of this  Agreement, "business  day"
means any day on which the New York Stock Exchange is open for trading.

     If the foregoing is in accordance with your understanding of our agreement,
sign and return to us the enclosed duplicate hereof, whereupon it will become a
binding agreement between the Company and the several Underwriters in accordance
with its terms.

                                                      Very truly yours,

                                                      ILLINOIS TOOL WORKS INC.


                                                      By: /s/ Jon C. Kinney
                                                         ----------------------
                                                         Jon C. Kinney
                                                         Senior Vice President &
                                                         Chief Financial Officer



The foregoing Underwriting Agreement is confirmed and accepted by us in Chicago,
  Illinois, acting on behalf of ourselves, the other Representatives (if any),
  and the several Underwriters (if any) named in the annexed Schedule II,
  as of the date first above written.

SALOMON SMITH BARNEY INC.
MERRILL LYNCH, PIERCE, FENNER & SMITH
          INCORPORATED
FIRST CHICAGO CAPITAL MARKETS, INC.

By:  SALOMON SMITH BARNEY INC.


     By: /s/ Thomas J. Sullivan
        ---------------------------
        Thomas J. Sullivan



                                       19
   20


                                   SCHEDULE I

UNDERWRITING AGREEMENT DATED February 19, 1999

REGISTRATION STATEMENT NO. 333-70691

REPRESENTATIVES:                         Salomon Smith Barney Inc.
                                         Merrill Lynch, Pierce, Fenner & Smith
                                                   Incorporated
                                         First Chicago Capital Markets, Inc.


TITLE, PURCHASE PRICE AND DESCRIPTION OF SECURITIES:



                                          
       Title:                                5 3/4% Notes due 2009

       Aggregate Principal Amount:           $500,000,000

       Price to Public:                      99.931%

       Purchase Price by Underwriter
          (include accrued interest or
       amortization if applicable):          99.281%

       Maturity:                             March 1, 2009

       Interest Rate:                        5 3/4%

       Interest Payment Dates:               March 1 and September 1

       Regular Record Dates:                 February 15 and August 15

       Redemption Provisions:                At the Company's option at any time at a price
                                             equal to the greater of par or a make-whole amount
                                             calculated on the basis of 12.5 basis
                                             points over the applicable Treasury Rate

       Sinking Fund Provisions:              None
       Other Provisions:                     None

SALE AND DELIVERY PROVISIONS UNDER SECTION 3:

       Obligation to Purchase is:            several and not joint [X]


   21



                                          
                                             several and not joint;
                                             provided, however that,
                                             notwithstanding the
                                             provisions of Section 9 of
                                             the Underwriting Agreement,
                                             the Representative(s)
                                             listed above will, subject
                                             to the terms and conditions
                                             hereof, purchase or cause
                                             to be purchased any
                                             Securities which any
                                             defaulting Underwriter or
                                             Underwriters have agreed
                                             but failed or refused to
                                             purchase pursuant to
                                             Section 3 hereof [_]

                                             joint and several [_]

       Payment to Be Made in:                New York Clearinghouse (same day) funds [_]
                                             or Federal (same day) funds [X]

       Delivery of Securities:               Physical delivery to Underwriters through
                                             Representatives [_]

                                             or delivery to Underwriters
                                             through facilities of DTC
                                             by delivery to DTC of one
                                             or more definitive global
                                             securities in book-entry
                                             form [X]

CLOSING DATE, TIME AND LOCATION:             9:00 a.m., February 24, 1999, at the offices of
                                             Gardner, Carton & Douglas, 321 North Clark Street,
                                             Chicago, Illinois  60610

ADDRESS FOR NOTICE TO REPRESENTATIVES:       Salomon Smith Barney Inc.
                                             Merrill Lynch, Pierce, Fenner & Smith
                                                       Incorporated
                                             First Chicago Capital Markets, Inc.
                                             c/o Salomon Smith Barney Inc.
                                             390 Greenwich Street
                                             4th Floor
                                             New York, NY 10013


                                       2
   22



                                  SCHEDULE II



                                                                   PRINCIPAL
              UNDERWRITERS                                          AMOUNT
              ------------                                         ---------
                                                                
     Salomon Smith Barney Inc.                                     $250,000,000
     Merrill Lynch, Pierce, Fenner & Smith                          150,000,000
                 Incorporated
     First Chicago Capital Markets, Inc.                            100,000,000
                                                                    -----------
                  Total                                            $500,000,000
                                                                    ===========


   23

                                        
                                  SCHEDULE III

                           DELAYED DELIVERY CONTRACT

                                                                            , 19

[Insert name and address  of lead Representative]

Ladies and Gentlemen:

     The undersigned hereby agrees to purchase from Illinois Tool Works Inc.
(the "Company"), and the Company agrees to sell to the undersigned, on [ ], 19 ,
(the "Delivery Date"), $[ ] principal amount of the Company's [ ] (the
"Securities") offered by the Company's Final Prospectus dated [ ], 19 , receipt
of a copy of which is acknowledged, at a purchase price of [ ]% of the principal
amount thereof, plus accrued interest, if any, thereon from [ ], 19 , to the
date of payment and delivery, and on the further terms and conditions set forth
in this contract.

     Payment for the Securities to be purchased by the undersigned shall be made
on or before 11:00 AM on the Delivery Date to or upon the order of the Company
in New York Clearinghouse (same day) funds or Federal (same day) funds, as
specified in Schedule I to the Underwriting Agreement referred to in the Final
Prospectus mentioned above, at your office or at such other place as shall be
agreed between the Company and the undersigned upon delivery to the undersigned
of the Securities in definitive fully registered form and in such authorized
denominations and registered in such names as the undersigned may request by
written communication addressed to the Company not less than five full business
days prior to the Delivery Date. If no request is received, the Securities will
be registered in the name of the undersigned and issued in a denomination equal
to the aggregate principal amount of Securities to be purchased by the
undersigned on the Delivery Date.

     The obligation of the undersigned to take delivery of and make payment for
Securities on the Delivery Date, and the obligation of the Company to sell and
deliver Securities on the Delivery Date, shall be subject to the conditions (and
neither party shall incur any liability by reason of the failure thereof) that
(i) the purchase of Securities to be made by the undersigned, which purchase the
undersigned represents is not prohibited on the date hereof, shall not on the
Delivery Date be prohibited under the laws of the jurisdiction to which the
undersigned is subject, and (ii) the Company, on or before the Delivery Date,
shall have sold to certain underwriters (the "Underwriters") such principal
amount of the Securities as is to be sold to them pursuant to the Underwriting
Agreement referred to in the Final Prospectus mentioned above. Promptly after
completion of such sale to the Underwriters, the Company will mail or deliver to
the undersigned at its address set forth below notice to such effect,
accompanied by a copy of the opinion of counsel for the Company delivered to the
Underwriters in connection therewith. The obligation of the undersigned to take
delivery of and make payment for the Securities, and the obligation of the
Company to cause the Securities to be sold and delivered, shall not be affected 

   24


by the failure of any purchaser to take delivery of and make payment for the
Securities pursuant to other contracts similar to this contract.

     This contract will inure to the benefit of and be binding upon the parties
hereto and their respective successors, but will not be assignable by either
party hereto without the written consent of the other.

     It is understood that acceptance of this contract and other similar
contracts is in the Company's sole discretion and, without limiting the
foregoing, need not be on a first come, first served basis. If this contract is
acceptable to the Company, it is required that the Company sign the form of
acceptance below and mail or deliver one of the counterparts hereof to the
undersigned at its address set forth below. This will become a binding contract
between the Company and the undersigned, as of the date first above written,
when such counterpart is so mailed or delivered.

     This agreement shall be governed by and construed and enforced in
accordance with, the internal laws of the State of Illinois.

                                              Very truly yours,


                                              (Name of Purchaser)

                                              By 
                                                 ------------------------------
                                                (Signature and Title of Officer)


                                                (Address)

Accepted:
ILLINOIS TOOL WORKS INC.

By
  ----------------------------
   (Authorized Signature)