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                                                                   Exhibit 10.28

                                                             [Execution Version]

                       FIRST AMENDMENT TO CREDIT AGREEMENT

       This First Amendment to Credit Agreement dated as of March 4, 2003, (this
"Amendment") is among Cooper Cameron Corporation, a Delaware corporation
("Parent"); Cooper Cameron (U.K.) Limited, a company formed under the laws of
the United Kingdom, Cameron GmbH, a Gesellschaft mit beschrankter Haftung formed
under the laws of the Federal Republic of Germany, Cooper Cameron (Singapore)
Pte. Ltd., a private limited company formed under the laws of the Republic of
Singapore, and Cooper Cameron Canada Ltd., a corporation formed under the laws
of Alberta, Canada (the "Borrowing Subsidiaries;" and together with the Parent,
the "Borrowers"); the Lenders (as defined below) executing this Agreement; and
Bank One, NA, as Agent (the "Agent").

                                  INTRODUCTION

       Reference is made to the 364-Day Credit Agreement dated as of March 6,
2002 (as modified, the "Credit Agreement"), among the Parent, the Borrowing
Subsidiaries, the Lenders, the Syndication and Documentation Agents (as defined
therein) and the Agent. The Parent, the Borrowing Subsidiaries, the Lenders, and
the Agent have agreed to extend the facility termination date under the Credit
Agreement in accordance with the terms set forth herein. Capitalized terms used
herein but not defined herein shall have the meanings specified by the Credit
Agreement.

       Therefore, in connection with the foregoing and for other good and
valuable consideration, the Parent, the Borrowing Subsidiaries, the Lenders, and
the Agent hereby agree as follows:

       Section 1.    Amendments to Credit Agreement.

       (a)    Article I of the Credit Agreement is amended by replacing the
definition of "Commitment" in its entirety to read as follows:

           "Commitment" means, for each Lender, the obligation of
           such Lender to make Revolving Loans to the Borrowers
           in an aggregate amount not exceeding the amount set
           forth opposite its signature to the First Amendment to
           Credit Agreement dated as of March 4, 2003, among the
           Borrowers, the Lenders parties thereto, and the Agent,
           as it may be modified as a result of any assignment
           that has become effective pursuant to Section 12.3.2
           or as otherwise modified from time to time pursuant to
           the terms hereof.

       (b)    Article I of the Credit Agreement is amended by replacing the
definition of "Facility Termination Date" in its entirety to read as follows:

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           "Facility Termination Date" means July 7, 2003, or any
           earlier date on which the Aggregate Commitment is
           reduced to zero or otherwise terminated pursuant to
           the terms hereof.

       (c)    The Credit Agreement is amended by replacing Schedule 1 thereto
with the Schedule 1 attached hereto.

       Section 2.    Representations and Warranties. The Borrowers represent and
warrant that (a) the execution, delivery and performance of this Amendment are
within the corporate power and authority of the Borrowers and have been duly
authorized by appropriate proceedings, (b) this Amendment constitutes a legal,
valid, and binding obligation of the Borrowers enforceable in accordance with
its terms, except as limited by applicable bankruptcy, insolvency,
reorganization, moratorium or similar laws affecting the rights of creditors
generally and general principles of equity, (c) no Unmatured Default or Default
is continuing, and (d) the representations and warranties set forth in the
Credit Agreement are true and correct as of the date of this Agreement.

       Section 3.    Effectiveness. This Amendment shall become effective as of
March 5, 2003, and the Credit Agreement shall be amended as provided herein as
of such effective date, upon the satisfaction of the following conditions
precedent:

       (a)    the Borrowers, the Agent, and Lenders holding Commitments
aggregating at least $100,000,000 shall have delivered duly and validly executed
originals of this Amendment to the Agent,

       (b)    the Parent shall have delivered to the Agent copies, certified by
the Secretary or Assistant Secretary of the Parent, of its Board of Directors'
resolutions authorizing the execution and delivery of this Amendment;

       (c)    the representations and warranties in this Amendment shall be true
and correct; and

       (d)    payment of the fees described in the fee letter dated as of
February 28, 2003, between the Parent, the Arranger, and the Agent.

       Upon effectiveness of this Amendment as provided above, the Lenders
parties to the Credit Agreement shall be those Lenders that have delivered duly
and validly executed originals of this Amendment, and the Aggregate Commitment
shall be the aggregate Commitments of such Lenders. Any lender party to the
Credit Agreement that does not deliver duly and validly executed originals of
this Amendment prior to March 5, 2003, shall cease to be a Lender under the
Credit Agreement as of such date, and shall have no further rights or
obligations thereunder, other than the right to receive repayment of its
Revolving Loans, if any, outstanding on such date and fees accrued prior to such
date, and rights and obligations that are expressly stated to survive payment of
the Obligations and termination of the Credit Agreement.

       In addition, upon effectiveness of this Amendment as provided above, any
outstanding Revolving Loans made by any lender that ceases to be a Lender under
the Credit Agreement at such time shall be repaid in full, together with unpaid
interest and fees accrued thereon through

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such date. Any Revolving Loans outstanding on such date will be reallocated by
the Administrative Agent so that each remaining Lender holds its Pro Rata Share
of the outstanding Obligations.

       Section 4.    Choice of Law. This Agreement shall be governed by and
construed and enforced in accordance with the laws of the State of New York.

       Section 5.    Counterparts. This Agreement may be signed in any number of
counterparts, each of which shall be an original, and may be executed and
delivered by telecopier.

       EXECUTED as of the date first above written.

                                          COOPER CAMERON CORPORATION



                                          By: __________________________________
                                          Name: Michael C. Jennings
                                          Title: Vice President & Treasurer


                                          COOPER CAMERON (U.K.) LIMITED
                                          CAMERON GMBH
                                          COOPER CAMERON (SINGAPORE) PTE. LTD.
                                          COOPER CAMERON CANADA LTD.



                                          By: __________________________________
                                          Name: Michael C. Jennings
                                          Title: Attorney-in-fact

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Commitment                                BANK ONE, NA,
$15,000,002                               individually and as Agent

US Swing Line Commitment
$15,000,000

                                          By: __________________________________
Canadian Swing Line Election              Name: Helen A. Carr
$10,000,000                               Title: First Vice President

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Commitment                                CREDIT LYONNAIS NEW YORK BRANCH,
$13,333,333                               individually and as Syndication Agent


                                          By: __________________________________
                                          Name: ________________________________
                                          Title: _______________________________

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Commitment                               THE ROYAL BANK OF SCOTLAND PLC,
$13,333,333                              individually and as Documentation Agent


                                         By: ___________________________________
                                         Name: _________________________________
                                         Title: ________________________________

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Commitment                               THE BANK OF NOVA SCOTIA,
$13,333,333                              individually and as Documentation Agent

                                         By: ___________________________________
                                         Name: _________________________________
                                         Title: ________________________________

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Commitment                               ABN AMRO BANK, N.V.,
$13,333,333                              individually and as Documentation Agent


                                         By: ___________________________________
                                         Name: Stuart Murray
                                         Title: Group Vice President


                                         By: ___________________________________
                                         Name: Jeffery White
                                         Title: Vice President

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Commitment                                DEN NORSKE BANK ASA
$11,666,666


                                          By: __________________________________
                                          Name: ________________________________
                                          Title: _______________________________


                                          By: __________________________________
                                          Name: Nils Fykse
                                          Title: Senior Vice President

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Commitment                                BANK OF AMERICA, N.A.
$10,000,000


                                          By: __________________________________
                                          Name: Claire Liu
                                          Title: Managing Director

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Commitment                                THE NORTHERN TRUST COMPANY
$10,000,000

                                          By: __________________________________
                                          Name: Eric Dybing
                                          Title: Second Vice President