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                                                                   EXHIBIT 10.46

                                    AMENDMENT

                                     TO THE

                   EMPLOYEE'S RETIREMENT PLAN OF AMETEK, INC.

                                 AMENDMENT NO. 4

         WHEREAS, there was adopted and made effective as of December 29, 1942,
the Employee's 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 the Board of Directors
of AMETEK, Inc. ("AMETEK") may amend the Plan at any time, and from time to
time; and

         WHEREAS, AMETEK now desires to make certain amendments necessary to
secure a favorable letter of determination with respect to the Plan's
tax-qualified status;

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

         FIRST: The third sentence of Section 1.11 of the Plan is hereby amended
to read, in its ----- entirety, as follows:

                  "In determining the "Compensation" of an Employee for purposes
         of this limitation for years prior to January 1, 1997, the aggregation
         rules of Section 414(q)(6) of the Code (as in effect prior to January
         1, 1997) shall apply to any Employee who is a member of a family of a
         5% owner (within the meaning of Section 416(i) of the Code) or a Highly
         Compensated Employee (as defined in Section 414(q) of the Code and as
         such definition is applied under other qualified retirement plans of
         the Employer) in the group consisting of the 10 employees paid the
         highest compensation."

                  SECOND: The last sentence of Section 1.18 of the
         Plan is hereby amended to read, in its entirety, as follows:

                  "Notwithstanding the foregoing, the term "Employee" shall not
         include any person whom the Employer determines, in its sole discretion
         based on the criteria set forth in Treas. Reg. Section 31.3401(c)-1, is
         not a common law employee. If a person who is not classified as an
         Employee otherwise satisfies the requirements of this Section 1.18 and
         is subsequently reclassified by the Employer as an



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         Employee, such person, for purposes of this Plan, shall be deemed an
         Employee from the later of the actual or the effective date of such
         reclassification."

         THIRD: Section 3.6 of the Plan is hereby amended by adding a sentence
at the conclusion thereof to read, in its entirety, as follows:

                  "Effective December 12, 1994, notwithstanding anything in this
         Plan to the contrary, Credited Service with respect to periods of
         qualified military service will be provided in accordance with Section
         414(u) of the Code."

         FOURTH: Section 4.4(a) of the Plan is hereby amended to substitute the
term "Credited Service" for the term "Vesting Service" in the seventh line
thereof.

         FIFTH: Section 4.6(b) of the Plan is hereby amended to read, in its
entirety, as follows:

                  "(b) Form of Payment. If the annual benefit is paid in a form
         other than a straight life annuity or a Qualified Joint and Survivor
         Annuity, the limitations of this Section 4.6 shall apply to the annual
         benefit by adjusting it so that it is the actuarial equivalent of a
         straight life annuity using an interest rate of 5% or the rate
         specified in Section 1.2, whichever is greater, and the mortality table
         described in Section 417(e)(3) of the Code."

         SIXTH: Section 4.6(c) of the Plan is hereby amended to read, in its
entirety, as follows:

                  "(c) Adjustment of Limitation. If payment of the annual
         benefit begins before the Participant or Former Participant attains his
         Social Security Retirement Age, the $90,000 limit contained in
         Subsection (a)(i) shall be adjusted so that it is the actuarial
         equivalent of an annual benefit of $90,000, multiplied by the
         Adjustment Factor, beginning at the Participant's or Former
         Participant's Social Security Retirement Age. The adjustment provided
         for in the preceding sentence shall be consistent with the reduction
         for old-age insurance benefits commencing before the Social Security
         Retirement Age under the Social Security Act for benefits that begin to
         be paid on or after age 62 using the mortality table described in
         Section 417(e)(3) of the Code, and the interest rate assumption used in
         adjusting the benefit for years prior to age 62 shall not be less than
         the greater of 5% or the rate specified in Section 1.2. If payment of
         the annual benefit of a Participant or Former Participant begins after
         the Participant or Former Participant attains his Social Security
         Retirement Age, the $90,000 limit contained in Subsection (a)(i) shall
         be adjusted so that it is the actuarial equivalent of a benefit of
         $90,000, multiplied by the Adjustment Factor, beginning at his Social
         Security Retirement Age; provided that the interest rate assumption
         used for such calculation shall not be greater than the lesser of 5% or
         the rate specified in Section 1.2."




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         SEVENTH: Section 5.11(b) of the Plan is hereby amended by adding a
sentence at the conclusion thereof to read, in its entirety, as follows:

                  "If distribution of benefit is considered to have commenced
         before the death of the Participant (as determined under Section
         401(a)(9) of the Code and the regulations thereunder), any remaining
         interest will be distributed at least as rapidly as under the method of
         distribution in effect at the time of the Participant's death."

         EIGHTH: The first sentence of Section 9.6(a) of the Plan is hereby
amended to read, in its entirety, as follows:

                  "In the event of Plan termination, the benefit payable to any
         highly compensated employee or any highly compensated former employee
         (as defined in Section 414(q) of the Code and as such definition is
         applied under other qualified retirement plans of the Employer) shall
         be limited to a benefit that is nondiscriminatory under Section
         401(a)(4) of the Code."

         NINTH: The provisions of this Amendment shall be effective as of
January 1, 1997.

         IN WITNESS WHEREOF, AMETEK has caused these presents to be executed, in
its corporate name, by its duly authorized officer, and its corporate seal to be
affixed on this 27th day of July, 1999.



                                     AMETEK, Inc.

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

Attest:

/s/ Kathryn E. Londra
---------------------
(Seal)