EXHIBIT 10.7


                              FIRST AMENDMENT TO
                      BENTHOS, INC. 401(K) RETIREMENT PLAN
            as Amended and Restated Effective as of November 5, 1993


     AMENDMENT adopted this 11th day of April 1997, by Benthos, Inc.
(hereinafter referred to as the "Company"):


                                  WITNESSETH:
                                  ---------- 

     WHEREAS, the Company has heretofore adopted a defined contribution plan
known as the "Benthos, Inc. 401(k) Retirement Plan", originally effective as of
July 1, 1987 and subsequently amended and restated said Plan in the form of the
IDS Nonstandardized (S)401(k) Profit Sharing Plan Prototype, most recently
effective as of November 5, 1993 (hereinafter referred to as the "Plan"); and

     WHEREAS, the Company, pursuant to Section 13.02 of the Plan, has reserved
the right to amend the Plan at any time by vote of its Board of Directors; and

     WHEREAS, the Company wishes to amend further the Plan in order to change
the eligibility requirements for a reemployed participant.

     NOW, THEREFORE, effective as of October 1, 1996, the Plan is hereby amended
as follows:

     1. Section 2.03 of the Adoption Agreement and the Basic Plan document shall
not apply and the following Section 2.03 shall be substituted therefor:

2.03 Break in Service - Participation
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     (a) A Participant whose employment has terminated and who recommences
employment without incurring a Break in Service shall be eligible to participate
immediately in the Plan as of the date on which he first subsequently renders an
Hour of Service.

     (b) A Participant who has terminated employment and incurred a Break in
Service will be eligible to commence Deferral Contributions immediately upon his
re-employment.

     (c) (i) For purposes of determining the eligibility of a re-employed former
Participant who has incurred a Break in Service to share in Employer matching
contributions, designated qualified nonelective contributions, discretionary
contributions and allocation of Participant forfeitures, Years of Service prior
to the Break in Service will not be taken into account until the former
Participant has completed a Year of Service after returning to employment. The
Employee will receive credit for a Year of Service following re-employment if,
during the 12-consecutive month period beginning on the Employee's "re-
employment commencement 

                                      -1-

 
date" the Employee is credited with 1,000 Hours of Service. If the Participant
fails to complete 1,000 Hours of Service within such period, the re-employed
Participant will be credited with a Year of Service if, during any Plan Year
beginning with the Plan Year which includes the first anniversary of the "re-
employment commencement date", he or she is credited with 1,000 Hours of
Service.

     (ii)  The "re-employment commencement date" is the first day on which the
employee is credited with an Hour of Service for the performance of duties after
the first eligibility computation period in which the Employee incurs a one year
Break in Service.

     (iii)  If a former Participant who has incurred a Break in Service
completes a Year of Service in accordance with this paragraph (c), his or her
eligibility to share in Employer matching contributions, designated qualified
nonelective contributions, discretionary contributions and allocation of
Participant forfeitures will begin as of first Entry Date following the
completion of such Year of Service.

     2. Section 3.06 of the Adoption Agreement is amended to read as set forth
on the following page:

                                      -2-

 
        Allocation of forfeited excess aggregate contributions. In lieu of the
        preceding paragraph the Advisory Committee will allocate any forfeited
        excess aggregate contributions (as described in Section 14.09):

        [X] (c) To reduce Employer matching contributions for the Plan Year
                following the Plan Year for which the Employer made the matching
                contributions.

        [_] (d) As Employer discretionary matching contributions for the Plan
                Year following the Plan Year for which the Employer made the
                matching contribution, except the Advisory Committee will not
                allocate these forfeitures to the Highly Compensated Employees
                who incurred the forfeitures.

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3.06    Accrual of Benefit.

        Compensation taken into account. For the Plan Year in which the Employee
        first becomes a Participant, the Advisory Committee will determine the
        allocation under Option (b), of Adoption Agreement Section 3.04 by
        taking into account:(Choose one)

        [_] (a) The Employee's Compensation for the entire Plan Year.

        [X] (b) The Employee's Compensation for the portion of the Plan Year in 
                which the Employee actually is a Participant in the Plan.

        This election regarding Compensation also applies to the allocation of 
        the designated qualified nonelective contribution.

        Hours of Service requirement. The minimum number of Hours of Service a
        Participant must complete during a Plan Year in order to receive an
        allocation of the matching contributions, designated qualified
        nonelective contributions, discretionary contributions and Participant
        forfeitures, if any, for the Plan Year is:

        [_] (c) One Hour of Service.

        [_] (d) 1,000 Hours of Service.

        [X] (e) Other (specify, but the number may not exceed 1,000) one Hour of
Service for matching contributions and 1,000 Hours of Service for designated 
qualified non-elective contributions, discretionary contributions and 
participant forfeitures.
        [X] (f) No Hour of Service requirement if the Participant terminates 
                employment during the Plan Year on account of:

                [X] (1) Death.

                [X] (2) Disability.

                [X] (3) Early Retirement (if applicable), or attainment of
                        Normal Retirement Age in the current Plan Year or in a
                        prior Plan Year.

        [Note:  The Employer may use Option (e) to designate a different Hours 
        of Service condition for  a particular type of Employer contribution.]

        Employment Requirement. A Participant who, during a particular Plan
        Year, completes the Hour of Service condition selected under this
        Adoption Agreement Section 3.06: (Choose at least one)

        [X] (g) Will share in the allocation of Employer contributions and
                Participant forfeitures, if any, for that Plan Year without
                regard to whether he is employed by the Employer on the
                Accounting Date of that Plan Year, except for the allocation
                of:

                [_] (1) No exceptions.

                [_] (2) Matching contributions (including forfeitures applied to
                        reduce Employer matching contributions).

                [X] (3) Discretionary contributions and Participant forfeitures
                        (other than forfeitures applied to reduce Employer
                        matching contributions).


 
     In all other respects the terms of the Plan remain unchanged and in full 
force and effect.

     IN WITNESS WHEREOF, the undersigned Company has caused this First Amendment
to be executed by its duly authorized officer as of the day and year set forth 
above.


                                          BENTHOS, INC.


                                          By: /s/ JOHN L. COUGHLIN
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