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                                                                 Exhibit 4.5(a)


                               FIRST AMENDMENT TO
                  THIRD AMENDED AND RESTATED CREDIT AGREEMENT


     THIS FIRST AMENDMENT (this "Amendment") is entered into as of April ___,
1997, among IDEX Corporation, a Delaware corporation (the "Company"), the
several financial institutions from time to time party to the Credit Agreement
(as defined herein) (collectively, the "Banks"; individually, a "Bank"), and
Bank of America Illinois, as agent for the Banks.

                                   BACKGROUND

     WHEREAS, the Company, the Banks and the Agent have entered into that
certain Third Amended and Restated Credit Agreement dated as of July 17, 1996
(as the same may be further amended or modified from time to time, the "Credit
Agreement") and the Loan Documents referred to in the Credit Agreement;

     WHEREAS, the Company, the Banks and the Agent have determined that the
Credit Agreement should be amended in certain respects and to make certain
other changes agreed to by the parties.

     NOW, THEREFORE, the parties hereto hereby agree as follows:

  1. Definitions.  Capitalized terms used but not otherwise defined herein
shall have the meanings ascribed to such terms in the Credit Agreement.


  2. Certain Amendments to Credit Agreement.  The Credit Agreement is hereby
amended, effective on the date this Amendment becomes effective in accordance
with Section 4 hereof, as follows:


  2.1 Section 1.01 of the Credit Agreement is hereby amended by adding the
following definitions in their proper alphabetical order:

      "Domestic EBITDA" means EBITDA less Foreign EBITDA and less any other
      portion of EBITDA derived by the Company or its Subsidiaries from any
      assets located outside the United States.

      "Foreign EBITDA" means, for any period, for the Foreign Subsidiaries and
      their Subsidiaries on a consolidated basis (as if one corporation),
      determined in accordance with GAAP, the sum of (a) Consolidated Net
      Income of such Persons for such period plus (b) all amounts treated as
      expenses for interest to the extent included in the determination of such
      Consolidated Net Income plus (c) all accrued taxes on or measured by
      income to the extent included in the determination of such Consolidated
      Net Income plus (d) all amounts treated as expenses for depreciation or
      the amortization of intangibles of any kind to the extent included in the
      determination of Consolidated Net Income.



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  2.2 Section 8.04(n), clause 3 of the Credit Agreement is hereby deleted in
its entirety and amended to read as follows:

      "(3) if the Person to be acquired would be a Material Subsidiary of the
      Company upon completion of the Acquisition or if the assets to be
      acquired have a net book value in excess of 5% of the consolidated total
      assets of the Company, based upon the Company's most recent annual or
      quarterly financial statements delivered to the Agent under Section 7.01,
      then not less than 10 days prior to the consummation of such Acquisition,
      the Company shall provide to the Agent annual financial statements
      (audited, if available) and unaudited interim financial statements for
      such Person, pro forma financial projections for such Person and for the
      Company on a consolidated basis giving effect to such Acquisition, all in
      such detail as shall be reasonably satisfactory to the Agent,"

  2.3 Section 8.15 of the Credit Agreement is hereby deleted in its entirety
and amended to read as follows:

      "8.15 Foreign Operations.  The Company shall generate Domestic EBITDA
      equal to or in excess of $75,000,000 and maintain total assets in the
      United States equal to or in excess of $300,000,000.

  3. Conditions to Effectiveness of this Amendment.  This Amendment shall
become effective upon the satisfaction of the following conditions:


  3.1 Executed Amendment.  Receipt by the Agent of duly executed counterparts of
this Amendment from the Company and the Banks; and


  3.2 Miscellaneous.  Receipt by the Agent of such other documents,
certificates, instruments or opinions as may reasonably be requested by it.


  4.  Certain Representations and Warranties by the Company.  In order to induce
the Banks and the Agent to enter into this Amendment, the Company represents
and warrants to the Banks and the Agent that:


  4.1 Authority.  The Company has the right, power and capacity and has been
duly authorized and empowered by all requisite corporate and shareholder action
to enter into, execute, deliver and perform this Amendment and the Credit
Agreement as amended hereby.


  4.2 Validity.  This Amendment and the Credit Agreement as amended hereby have
each been duly and validly executed and delivered by the Company and
constitutes its legal, valid and binding obligations, enforceable against the
Company in accordance with its respective terms, except as enforcement thereof
may be subject to the effect of any applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting creditors' rights
generally and general principles of equity (regardless of whether such
enforcement is sought in a proceeding in equity or at law or otherwise).

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  4.3 No Conflicts.  The Company's execution, delivery and performance of this
Amendment and the Credit Agreement as amended hereby does not and will not
violate its Certificates or Articles of Incorporation or Bylaws, any law, rule,
regulation, order, writ, judgment, decree or award applicable to the Company or
any contractual provision to which the Company is party or to which the Company
or any of its Subsidiaries are subject.


  4.4 Approvals.  No authorization or approval or other action by, and no notice
to or filing or registration with, any Governmental Authority or regulatory
body (other than those which have been obtained and are in force and effect) is
required in connection with the Company's execution, delivery and performance
of this Amendment and the Credit Agreement as amended hereby.


  4.5 Incorporated Representations and Warranties.  All representations and
warranties contained in the Loan Documents are true and correct in all material
respects with the same effect as though such representations and warranties had
been made on and as of the date hereof and the effective date hereof, except as
to any representations or warranties which expressly relate to an earlier date,
in which event, such representations and warranties are true as of such date.


  4.6 No Defaults.  No Default or Event of Default exists as of the date hereof
or will exist after giving effect to this Amendment.


  5.  Miscellaneous.  The parties hereto hereby further agree as follows:


  5.1 Further Assurances.  Each of the parties hereto hereby agrees to do such
further acts and things and to execute, deliver and acknowledge such additional
agreements, powers and instruments as any other party hereto may reasonably
require to carry into effect the purposes of this Amendment and the Credit
Agreement as amended hereby.


  5.2 Counterparts.  This Amendment may be executed in one or more counterparts,
each of which, when executed and delivered, shall be deemed to be an original
and all of which counterparts, taken together, shall constitute but one and the
same document with the same force and effect as if the signatures of all of the
parties were on a single counterpart, and it shall not be necessary in making
proof of this Amendment to produce more than one such counterpart.


  5.3 Headings.  Headings used in this Amendment are for convenience of
reference only and shall not affect the construction of this Amendment.


  5.4 Integration.  This Amendment and the Loan Documents constitute the entire
agreement among the parties hereto with respect to the subject matter hereof
and thereof.


  5.5 Governing Law.  THIS AMENDMENT SHALL BE DEEMED TO BE A CONTRACT MADE UNDER
THE LAWS OF THE STATE OF ILLINOIS, AND FOR ALL PURPOSES SHALL BE GOVERNED BY
AND CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE INTERNAL LAWS AND DECISIONS
OF SAID STATE,


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WITHOUT REGARD TO PRINCIPLES OF CONFLICTS OF LAWS.

  5.6 Binding Effect.  This Amendment shall be binding upon and inure to the
benefit of and be enforceable by the parties hereto and their respective
successors and assigns; provided, however, that the Company may not assign or
transfer its rights, interests or obligations hereunder without the prior
written consent of the Agent and all of the Banks.  Except as expressly set
forth to the contrary herein, this Amendment shall not be construed so as to
confer any right or benefit upon any Person other than the parties to this
Amendment and their respective successors and permitted assigns.


  5.7 Amendment; Waiver; Reaffirmation of Loan Documents.  The parties hereto
agree and acknowledge that nothing contained in this Amendment in any manner or
respect limits or terminates any of the provisions of the Credit Agreement or
the other Loan Documents other than as expressly set forth herein and further
agree and acknowledge that the Credit Agreement and each of the other Loan
Documents remain and continue in full force and effect and are hereby ratified
and reaffirmed in all respects.  No delay on the part of any Bank or the Agent
in exercising any of their respective rights, remedies, powers and privileges
under the Credit Agreement or any of the other Loan Documents or partial or
single exercise thereof, shall constitute a waiver thereof.  none of the terms
and conditions of this amendment may be changed, waived, modified or varied in
any manner, whatsoever, except in accordance with Section 11.01 of the Credit
Agreement.


  5.8 Reference to and Effect on the Credit Agreement and the other Loan
Documents.  Upon the effectiveness hereof, each reference in the Credit
Agreement to "this Agreement," "hereunder," "hereof," "herein," or words of
like import referring to the Credit Agreement and each reference in the other
Loan Documents to the "Credit Agreement," "thereunder," "thereof," or words of
like import referring to the Credit Agreement shall mean and be a reference to
the Credit Agreement as amended by this Amendment.  The Credit Agreement shall
be deemed to be amended wherever and as necessary to reflect the foregoing
amendments.



                            [signature page follows]








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     IN WITNESS WHEREOF, this Amendment has been duly executed and delivered as
of the date first above written.


                                         IDEX CORPORATION

 
                                         By: /s/ Douglas C. Lemos
                                            ---------------------------------
                                                 Douglas C. Lemos

                                         Title:  Treasurer
                                               ------------------------------


                                         Copy to:
                                         Kohlberg Kravis Roberts & Co.
                                         9 West 57th Street
                                         New York, NY 10019
                                         Attention: Michael T. Tokarz
 

 

                                         BANK OF AMERICA ILLINOIS, AS AGENT


                                         By: /s/ David L. Graham
                                            ---------------------------------
                                                 David L. Graham

                                         Title:  Vice President
                                               ------------------------------



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                                         BANK OF AMERICA ILLINOIS, AS A BANK


                                         By: /s/ Randolph T. Kohler
                                            ---------------------------------
                                                 Randolph T. Kohler

                                         Title: Senior Vice President
                                               ------------------------------


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                                         BANK OF SCOTLAND

                                         By: /s/ Annie Chin Tat
                                            --------------------------------
                                                 Annie Chin Tat

                                         Title:  Assistant Vice President
                                               -----------------------------


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                                         NATIONAL CITY BANK


                                         By: /s/ Brian J. Cullina
                                             -------------------------------
                                                 Brian J. Cullina
                                         Title:  Vice President
                                                ----------------------------


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                                         PNC BANK, NATIONAL ASSOCIATION


                                         By:  /s/ Karen C. Broz
                                            -------------------------------
                                                  Karen C. Broz

                                         Title:  Commercial Banking Officer
                                                ---------------------------


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                                         UNION BANK OF CALIFORNIA, N.A.,
                                         (SUCCESSOR IN INTEREST TO UNION BANK)


                                         By: /s/ Cary Moore
                                             --------------------------------
                                                 Cary Moore

                                         Title: Credit Officer Vice President
                                               ------------------------------





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                                         UNITED STATES NATIONAL BANK
                                         OF OREGON


                                         By: /s/ Monica J. Treacy
                                            ------------------------------
                                                 Monica J. Treacy

                                         Title: Assistant Vice President
                                               ---------------------------

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                                         THE HARRIS TRUST AND SAVINGS
                                         BANK CO.


                                         By: /s/ 
                                            ---------------------------------
                                         Title: Vice President
                                                -----------------------------