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                                                                   EXHIBIT 10.48
                                 AMENDMENT NO. 6

                                     TO THE

                           EMPLOYEES' RETIREMENT PLAN
                                 OF AMETEK, INC.


         WHEREAS, there was adopted and made effective as of December 29, 1942,
the Employees' Retirement Plan of AMETEK, Inc. (the "Plan"); and

         WHEREAS, the Plan was amended and restated in its entirety, effective
January 1, 1998; and

         WHEREAS, Section 9.2 of the Plan provides that AMETEK, Inc. ("AMETEK")
may amend the Plan at any time or from time to time; and

         WHEREAS, AMETEK now desires to amend the Plan in certain respects;

         NOW, THEREFORE, the Plan is hereby amended as follows:

         FIRST: A new Appendix XXXIII is hereby added to the Plan, to read in
its entirety as follows:

                                 APPENDIX XXXIII
                          SPECIAL PROVISIONS RELATING TO CERTAIN
               EMPLOYEES OF THE AEROSPACE DIVISION OF AMETEK, INC.

         1. The AMETEK, Inc. Aerospace Division Employees' Retirement Plan (the
         "Aerospace Plan") shall be merged into, and continued as part of the
         Plan effective as of the close of business, December 31, 1999 (the
         "Amendment Effective Date"), and the assets under the AMETEK, Inc.
         Employees' Master Retirement Trust allocable to the Aerospace Plan
         shall be transferred to the Plan as soon as practicable immediately
         thereafter.

         2. The provisions of this Appendix XXXIII shall apply to each active
         employee of the Aerospace Division of AMETEK, Inc. (the "Aerospace
         Division") who is a "Participant" as defined in the Aerospace Plan on
         the Amendment Effective Date and who becomes a Participant in the Plan
         on the Amendment Effective Date as a result of the merger of the
         Aerospace Plan with and into the Plan. Each such person shall be
         referred to as an "Aerospace Participant" for purposes of this Appendix
         XXXIII.

         3. Any former employee of the Aerospace Division who separated from
         service entitled to a deferred vested pension benefit as determined
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         under the terms of the Aerospace Plan or who is receiving a pension
         benefit as determined under the terms of the Aerospace Plan prior to
         the Amendment Effective Date (each a "Former Aerospace Participant") or
         any beneficiary of a Former Aerospace Participant who is receiving or
         becomes entitled to receive such benefits under the Aerospace Plan
         shall receive such benefits at the same times and in the same amounts
         as provided in the Aerospace Plan, determined under the terms of the
         Aerospace Plan as of the date the Former Aerospace Participant
         separated from service with the Aerospace Division, but payable from
         the Plan. Determinations, elections, designations and directions made
         by Former Aerospace Participants under the terms of the Aerospace Plan
         shall remain in effect under the Plan, unless changes, modified or
         otherwise revoked in accordance with the terms of the Plan.

         4. Each Aerospace Participant's benefits shall be determined in
         accordance with the provisions of the Plan; provided, however the
         following modifications shall apply:

                  (a) Section 1.1 (a) shall be modified by substituting
                  "Thirty-two and a half percent (32.5%) for "Thirty-two percent
                  (32%);

                  (b) Section 4.5(f) shall be modified by substituting for the
                  portion of the last sentence beginning with "a single sum
                  death benefit" the following: "a single sum death benefit in
                  the amount of $5,000 will be paid to his Beneficiary,
                  provided, however, that in the case of any Pensioner described
                  in this Subsection (f) who had directly transferred his
                  employment from GE to the Company on August 7, 1989 and who,
                  as of the August 7, 1989, had attained age 50 but had not
                  satisfied the requirements for eligibility to retire under the
                  GE Plan, the amount of the single sum death benefit payable to
                  a Pensioner's Beneficiary pursuant to this Subsection (f)
                  shall be $1,000.

                  (c) An Aerospace Participant who directly transferred his
                  employment from GE to AMETEK Aerospace Products, Inc. on
                  August 7, 1989, and who retires on or after his 60th birthday
                  and commences receiving a pension prior to his 65th birthday
                  pursuant to Section 4.2 or 4.3 shall be eligible for a
                  supplemental pension benefit if, as of August 7, 1989, (i) the
                  sum of such Participant's age (with each full month to be
                  counted as 1/12th of a year) and Credited Service totaled 50,
                  and (ii) such Aerospace Participant had not satisfied the
                  requirements for eligibility to retire under the GE Pension
                  Plan as of August 8, 1989. An Aerospace Participant's
                  supplemental pension benefit shall be in a monthly amount
                  equal to $190, and shall be payable commencing on the date on
                  which his pension commences pursuant to Section 4.2 or 4.3, as
                  the case may be, and continuing up to, but not including the
                  first day of the month in which he
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                  attains age 65 or, if earlier, the first day of the month
                  following the month in which he dies.

                  5. An Aerospace Participant's Vesting Service under the Plan
                  shall equal the sum of (i) his or her Vesting Service earned
                  under the Aerospace Plan up to the Amendment Effective Date
                  and (ii) his or her Vesting Service earned under the Plan
                  after the Amendment Effective Date. Notwithstanding the
                  foregoing, an Aerospace Participant shall not be credited with
                  more than one year of Vesting Service with respect to the 1999
                  calendar year or any other 12-month period.
 .
                  6. An Aerospace Participant's Credited Service under the Plan
                  shall equal the sum of (i) his or her Vesting Service earned
                  under the Aerospace Plan up to the Amendment Effective Date
                  and (ii) his or her Credited Service earned under the Plan
                  after the Amendment Effective Date. Notwithstanding the
                  foregoing, an Aerospace Participant shall not be credited with
                  more than one year of Credited Service with respect to the
                  1999 calendar year or any other 12-month period.

                  7. Except to the extent set forth above, defined terms used in
                  this Appendix XXXIII shall have the same meaning as used in
                  the Plan.



                  IN WITNESS WHEREOF, AMETEK has caused these presents to be
executed in its corporate name, by its duly authorized officer on this 22nd day
of December, 1999.

                                  AMETEK, Inc.

                                  By:  /s/ Donna F. Winquist
                                  ----------------------------------------------

Attest:

/s/ Kathryn E. Londra
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