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                                                                     EXHIBIT 10a

                              HUBBELL INCORPORATED



                              AMENDED AND RESTATED

                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN



                Restated and Amended, Effective December 8, 1999


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                              HUBBELL INCORPORATED

                     SUPPLEMENTAL EXECUTIVE RETIREMENT PLAN

                                Table of Contents

<TABLE>
<CAPTION>
                                                                                                             Page
                                                                                                             ----
<S>                        <C>                                                                            <C>
ARTICLE I                  PURPOSE.............................................................................1
                           -------
ARTICLE II                 DEFINITIONS.......................................................................1-2
                           -----------
ARTICLE III                EFFECTIVE DATE......................................................................3
                           --------------
ARTICLE IV                 ELIGIBILITY.......................................................................3-4
                           -----------
ARTICLE V                  RETIREMENT BENEFITS...............................................................4-6
                           -------------------
ARTICLE VI                 PAYMENT OF RETIREMENT BENEFITS....................................................7-8
                           ------------------------------
ARTICLE VII                DISABILITY BENEFIT................................................................8-9
                           ------------------
ARTICLE VIII               DEATH BENEFIT....................................................................9-11
                           -------------
ARTICLE IX                 FUNDING.........................................................................11-12
                           -------
ARTICLE X                  PLAN ADMINISTRATION................................................................12
                           -------------------
ARTICLE XI                 AMENDMENT AND TERMINATION..........................................................12
                           -------------------------
ARTICLE XII                MISCELLANEOUS PROVISIONS........................................................13-15
                           ------------------------
ARTICLE XIII               CHANGE OF CONTROL...............................................................16-20
                           -----------------
</TABLE>




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                                    ARTICLE I

                                     PURPOSE

1.1      The purpose of this Supplemental Executive Retirement Plan (the "Plan")
         is to provide monthly supplemental retirement income for a select group
         of officers and other key employees of Hubbell Incorporated (the
         "Employer"). It is intended to provide a retirement benefit which
         supplements the retirement benefit payable under the Hubbell
         Incorporated Retirement Plan for Salaried Employees and other such
         pension plans of Hubbell Incorporated and its subsidiaries as deemed
         appropriate by the Board of Directors in its sole and absolute
         discretion.

                                   ARTICLE II

                                   DEFINITIONS

2.1      "Accrued Deferred Vested Retirement Benefit" means the benefit
         described in Article 5.4.

2.2      "Accrued Vested Participant" means a Participant who has been credited
         with ten (10) or more years of Service.

2.3      "Average Earnings" means the annual average of the Participant's
         Earnings for any three (3) calendar years in his last ten (10) years of
         Service which produce the highest such average.

2.4      "Board of Directors" means the Board of Directors of Hubbell
         Incorporated.

2.5      "Compensation Committee" means the Compensation Committee of the Board
         of Directors.

2.6      "Early Retirement" means retirement under this Plan at a Participant's
         election, between the ages of 55 and 65.


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                                                                               2


2.7      "Earnings" means, with respect to a particular calendar year, the total
         of (a) cash earnings paid to a Participant in the form of base salary,
         (b) awards in respect of the prior calendar year (regardless of when
         paid) under the incentive compensation plan (annual bonus) by his
         Employer, and (c) any amount by which an Employee's base salary and
         annual bonus awards are reduced under any 401(k) plan or any flexible
         benefit plans under the Internal Revenue Code Sections 125 and 129
         maintained by the Employer, during the respective calendar year.

2.8      "Employee" means a person who is employed by the Employer on a regular,
         full-time basis.

2.9      "Employer" means Hubbell Incorporated, and its successor, and any of
         its subsidiaries so designated by the Board of Directors.

2.10     "Key Executive" means (a) (i) any Officer elected prior to May 1,1993
         and (ii) any other Employee who was so designated by the Compensation
         Committee prior to May 1, 1993, and (b) any Officer or other Employee
         who is so designated by the Compensation Committee on or after May 1,
         1993 and as to who the Compensation Committee has not withdrawn such
         designation.

2.11     "Normal Retirement" means retirement by a Participant under this Plan
         on the first day of the month coinciding with or next following his
         65th birthday.

2.12     "Officer" means the individual elected by the Board of Directors as
         provided in Article IV of the By-Laws of Hubbell Incorporated to any of
         the following offices: Chairman of the Board, President, Executive Vice
         President, Senior Vice President, Group Vice President, Vice President,
         Treasurer, Controller, or Secretary of Hubbell Incorporated.

2.13     "Participant" means a Key Executive.


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                                                                               3


2.14     "Plan" means the Hubbell Incorporated Supplemental Executive Retirement
         Plan.

2.15     "Postponed Retirement" means the Participant's actual retirement date
         after Normal Retirement.

2.16     "Service" means a Participant's entire period of employment with the
         Employer as an Officer and such other period of employment with the
         Employer as a Key Executive as designated and determined by the
         Compensation Committee.

2.17     "Spouse" shall mean the person to whom the Participant was lawfully
         married for at least one (1) year on the Participant's actual date of
         retirement (early, normal, postponed or disability, as the case may be)
         or termination from the Employer.

2.18     "Total Disability" means the Compensation Committee's determination
         that a Participant is totally and permanently disabled and can no
         longer perform his duties as a Key Executive of the Employer.

                                   ARTICLE III

                                 EFFECTIVE DATE

3.1      This Plan shall be effective as of April 1, 1980.

                                   ARTICLE IV

                                   ELIGIBILITY

4.1      Key Executives shall continue to be Participants until their Service
         with the Employer is terminated or they are no longer entitled to
         retirement or deferred vested benefits under this Plan, whichever is
         later. A Participant who has been credited with ten (10) or more years
         of Service becomes an Accrued Vested Participant eligible for an
         Accrued Deferred


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                                                                               4


         Vested Retirement Benefit. If a Participant is no longer a Key
         Executive, but remains an Employee, his accrued Service as a
         Participant shall not be forfeited.

                                    ARTICLE V

                               RETIREMENT BENEFITS

5.1      Normal Retirement Benefit. A Participant's Normal Retirement Benefit
         under this Plan, computed as a straight life annuity, shall equal (a)
         minus (b), where:

         (a)      Equals - Six (6%) percent multiplied times the number of full
                  years of a Key Executive's Service.

         In no event shall the percentage of benefit credit calculated under
         this Article 5.1 (a) exceed sixty (60%) percent. The appropriate
         percentage of benefit credit calculated under this Article 5.1 (a)
         shall then be multiplied by the Participant's Average Earnings.

         (b)      Equals - The benefits, if any, available from the following
                  sources:

                  (i)      any defined benefit pension plan or defined
                           contribution plan of the Employer which is qualified
                           under Section 401 of the Internal Revenue Code
                           (excluding, however: (a) any ancillary benefits such
                           as Medical or Transitional Supplements in the defined
                           benefit pension plans, and (b) any 401(k) plan
                           maintained by the Employer);

                  (ii)     any top-hat excess pension plan of the Employer; and

                  (iii)    any retirement benefits so designated and defined by
                           the Compensation Committee through a special
                           arrangement with the Employer.

         For purposes of determining the benefits available from any qualified
         defined benefit pension plan or qualified defined contribution plan of
         the Employer, it shall be assumed


<PAGE>   7
                                                                               5


         that the Participant commenced receiving his benefits under such plan
         on the fifteenth day of the month commencing after his actual
         retirement date.

5.2      Early Retirement Benefit. A Participant who elects to retire on or
         after age 55 shall be entitled to an early retirement benefit
         commencing on the date described in Article 6.1 hereof. The annual
         amount of the Early Retirement Benefit payable to a Participant who
         elects Early Retirement shall be an amount computed in accordance with
         Article 5.1 hereof except that the Early Retirement Benefit shall be
         based upon the Participant's years of Service up to his actual Early
         Retirement Date (the first day of any month elected by the Participant
         between the date the Participant attains age 55 and the date he attains
         age 65), with the amount reduced by three-tenths of one percent (3/10%)
         for each complete month by which the commencement date of his Early
         Retirement Benefit precedes his attainment of age 62 and by an
         additional two-tenths of one percent (2/10%) for each complete month by
         which the commencement date of his Early Retirement Benefit precedes
         his 60th birthday, provided, however, the Compensation Committee may,
         in its sole discretion, waive, in whole or in part, said early
         retirement reduction factors and, for purposes of determining the
         benefits available from any qualified defined benefit pension plan or
         qualified defined contribution plan of the Employer, it shall be
         assumed that the Participant commenced receiving his benefits under
         such plan on the earliest date the Participant could have retired under
         such plan.

5.3      Postponed Retirement. A Participant's Postponed Retirement Benefit
         under this Plan shall be the same amount that would have been payable
         had the Participant retired on his Normal Retirement Date. For purposes
         of determining the benefits available from any qualified defined
         benefit pension plan or qualified defined contribution plan of the



<PAGE>   8
                                                                               6


         Employer, it shall be assumed that the Participant commenced receiving
         his benefits under such plan on the fifteenth day of the month
         commencing after his actual retirement date.

5.4      Accrued Deferred Vested Retirement Benefit. Subject to Articles 12.4
         and 12.5 hereof, an Accrued Vested Participant whose employment with
         the Employer terminates on or after September 12, 1984, other than by
         normal, early, postponed, or disability retirement or death shall, if
         he has then completed ten (10) or more full years of Service, be
         entitled to a non-forfeitable Accrued Deferred Vested Retirement
         Benefit commencing on the date described in Article 6.1 hereof. The
         annual amount of the Accrued Deferred Vested Retirement Benefit payable
         to an Accrued Vested Participant shall be computed in accordance with
         Article 5.1 hereof except that the Accrued Deferred Vested Retirement
         Benefit shall be based upon the Accrued Vested Participant's Service as
         of the date of his termination of employment, with the amount reduced
         by three-tenths of one percent (3/10%) for each complete month by which
         the commencement date of his Accrued Deferred Vested Retirement Benefit
         precedes his Normal Retirement Date and by an additional two-tenths of
         one percent (2/10%) for each complete month by which the commencement
         date of his Accrued Deferred Vested Retirement Benefit precedes his
         60th birthday, provided, however, the Compensation Committee may, in
         its sole discretion, waive, in whole or in part, said reduction factors
         and, for purposes of determining the benefits available from any
         qualified defined benefit pension plan or qualified defined
         contribution plan of the Employer, it shall be assumed that the
         Participant commenced receiving his benefits under such plan on the
         first date that the Participant could have received deferred vested
         retirement benefits under such plan.


<PAGE>   9
                                                                               7


                                   ARTICLE VI

                         PAYMENT OF RETIREMENT BENEFITS

6.1      Payment of Benefits.

         (a)      Except as set forth herein and in Section 6.1(b) below, all
                  retirement benefits hereunder shall be payable in monthly
                  installments (on the fifteenth day of the month) equal to
                  one-twelfth (1/12th) of the annual amounts determined under
                  this Plan. A Participant's retirement benefit, if any,
                  hereunder shall be payable for the life of the Participant,
                  commencing (a) for normal, postponed or disability
                  retirements, on the fifteenth day of the month commencing
                  after his actual retirement date, (b) for Early Retirement, on
                  the fifteenth day of the month commencing after the
                  Participant's actual Early Retirement date and (c) for an
                  Accrued Vested Participant, on the fifteenth day of the month
                  commencing after the first date that the Accrued Vested
                  Participant may receive deferred vested retirement benefits
                  under the applicable defined benefit pension plan (qualified
                  under Section 401(a) of the Internal Revenue Code of 1986)
                  maintained by the Employer, or any successor defined benefit
                  pension plan. The Participant's last payment of retirement
                  benefits hereunder shall be made on the fifteenth day of the
                  month in which he dies unless the Participant has an eligible
                  surviving Spouse at his date of death, in which case survivor
                  benefit payments shall be made to said Spouse in accordance
                  with Article VIII hereof.

         (b)      In the case of a Participant who has attained age 61, he may
                  elect, by giving written notice to the Compensation Committee
                  at least one year prior to his Early Retirement at or after
                  age 62, Normal Retirement or Postponed Retirement, to


<PAGE>   10
                                                                               8


                  receive any applicable retirement and death benefit otherwise
                  payable under Section 5 and Section 8.2 hereof in the form of
                  a lump sum. Such lump sum shall be payable as soon as
                  practicable after the Participant's retirement date, and
                  calculated as follows:

                  (i)      Interest rate: Interest payable on 10 year U.S.
                           Treasury notes as of the October 1 preceding the
                           Participant's retirement date.

                  (ii)     Mortality Table: The Mortality Table being utilized
                           by the Hubbell Incorporated Retirement Plan for
                           Salaried Employees as of the October 1 preceding the
                           Participant's retirement date.

6.2      Payments Rounded to Next Higher Full Dollar. Each monthly payment which
         is computed in accordance with this Plan will, if not in whole dollars,
         be increased to the next whole dollar. Such rounding shall be made
         after applying any applicable reduction factors.

                                   ARTICLE VII

                               DISABILITY BENEFIT

7.1      Disability Benefit. If a Participant is deemed by the Compensation
         Committee to have incurred a Total Disability, he shall receive a
         disability retirement benefit hereunder commencing on the fifteenth day
         of the month commencing after the date he is deemed by the Compensation
         Committee to be so disabled. The annual amount of the Participant's
         Disability Retirement Benefit hereunder shall be computed as in Article
         5.1 hereof, but assuming that the Participant has been employed with
         the Employer until his Normal Retirement Date at the last rate of his
         Earnings in effect at the time he was deemed by the Compensation
         Committee to be permanently and totally disabled.


<PAGE>   11
                                                                               9


7.2      Medical Examination. Any Participant retired for Total Disability may
         be required by the Compensation Committee to submit to a medical
         examination at any time prior to his 65th birthday, but not more than
         once each year, to determine whether the Participant is eligible for
         continuance of the Disability Retirement Benefit provided hereunder.

                                  ARTICLE VIII

                                  DEATH BENEFIT

8.1      Pre-Retirement Death Benefit.

         (a)      If an Accrued Vested Participant or a former Accrued Vested
                  Participant whose benefit has not yet commenced dies, and he
                  is survived by a spouse to whom he was married throughout the
                  one-year period ending on the date of his death, such spouse
                  shall be entitled to receive a spouse's benefit described
                  herein, payable in the amount and manner prescribed in
                  subsections (b) and (c) of this Section 8.1.

         (b)      The spouse's benefit is an annuity for the life of the spouse
                  in an amount which is equal to the benefit the spouse would
                  have received under a joint and survivor annuity that provided
                  the spouse on the date of death of the Participant an annual
                  pension equal to 50 percent of the Participant's annual
                  pension if:

                  (i)      the Participant had retired on the day before his
                           death, in the case of a Participant who dies after he
                           is eligible for retirement, or

                  (ii)     the Participant had separated from service with the
                           Employer on the date of his death, survived to his
                           earliest retirement date, retired on such date, and
                           died on the day after such date, in the case of a
                           Participant who dies before he is eligible for
                           retirement.


<PAGE>   12
                                                                              10


         (c)      Payments of spouse's benefit shall commence as of the later of
                  (i) the first day of the month, following the Participant's
                  death; or (ii) the month following the date the Participant
                  would have attained the earliest age on which he could have
                  retired, provided the spouse survives to that date.

         (d)      For purposes of computing the spouse's benefit, actuarial
                  factors shall be used as are then applicable under the Hubbell
                  Incorporated Retirement Plan for Salaried Employees.

8.2      Post-Retirement Death Benefit. Unless such individual has elected to
         receive his benefit in a lump sum pursuant to Section 6.1 (b), if a
         Participant or Accrued Vested Participant dies while receiving
         retirement benefits under this Plan, a death benefit equal to fifty
         (50%) percent of the retirement benefit which the Participant or
         Accrued Vested Participant was receiving under this Plan immediately
         prior to his death shall be paid to his eligible surviving Spouse, if
         any. If, as of the date of the Participant's or Accrued Vested
         Participant's death, his eligible surviving Spouse, if any, is ten (or
         more) years younger than the Participant or Accrued Vested Participant,
         then the death benefit payable to said eligible surviving Spouse shall
         be actuarially reduced pursuant to the actuarial factors then
         applicable under the Hubbell Incorporated Retirement Plan for Salaried
         Employees. Notwithstanding anything contained herein to the contrary,
         in no event shall an eligible surviving Spouse receive in any year
         under this Plan more than the excess (if any) of thirty-three and
         one-third percent (33-1/3%) of the Participant's or Accrued Vested
         Participant's Average Earnings over the aggregate value (as determined
         by the Compensation Committee) of benefits receivable in such year
         under the Hubbell Incorporated Retirement Plan for Salaried Employees
         and any defined benefit pension plan


<PAGE>   13
                                                                              11


         or defined contribution plan of the Employer which is qualified under
         Section 401(a) of the Internal Revenue Code (excluding, however: (a)
         any ancillary benefits such as Medical or Transitional Supplements in
         the defined benefit pension plans, and (b) any 401(k) plan maintained
         by the Employer). Payments of said death benefit to the surviving
         Spouse shall commence to be paid on the fifteenth day of the month
         coinciding with or next following the Participant's or Accrued Vested
         Participant's death and shall continue until the Spouse dies.

                                   ARTICLE IX

                                     FUNDING

9.1      The Employer may enter into a trust agreement creating an irrevocable
grantor trust for the holding of cash and/or annuity contracts for pension
benefits accrued by the Participants under the Plan. Any assets of such trust
shall be subject to the claims of creditors of the Employer to the extent set
forth in the trust and Participants' interests in benefits under this Plan
shall only be those of unsecured creditors of the Employer. In the event of a
Change of Control, the Employer shall enter into a trust agreement creating an
irrevocable grantor trust for the holding of cash and/or annuity contracts in
respect of the pension benefits accrued by the Participants (whether current or
former) and in respect of the pension benefits provided to certain Employees
who shall be deemed to be Participants pursuant to written agreements with the
Employer; provided, further, that upon the occurrence of a Change of Control
Transaction, the Employer shall transfer to the trustee of the foregoing trust
the


<PAGE>   14
                                                                              12


maximum amount of assets estimated to be necessary to satisfy the Employer's
obligations hereunder, as in effect immediately prior to the Change of Control
Transaction.

                                    ARTICLE X

                               PLAN ADMINISTRATION

10.1     The general administration of this Plan and the responsibility for
         carrying out the provisions hereof shall be vested in the Compensation
         Committee. The Compensation Committee may adopt, subject to the
         approval of the Board of Directors, such rules and regulations as it
         may deem necessary for the proper administration of this Plan, and its
         decision in all matters shall be final, conclusive, and binding.

                                   ARTICLE XI

                            AMENDMENT AND TERMINATION

11.1     The Board of Directors of the Employer reserves in its sole and
         exclusive discretion the right at any time and from time to time to
         amend this Plan in any respect or terminate this Plan without
         restriction and without the consent of any Participant, Accrued Vested
         Participant, or Spouse, provided, however, that no amendment or
         termination of this Plan shall impair the right of any Participant,
         Accrued Vested Participant, or Spouse to receive benefits earned and
         accrued hereunder prior to such amendment or termination. The Board of
         Directors shall not terminate this Plan solely to accelerate benefits
         earned and accrued hereunder. Any amounts not currently payable to a
         Participant, Accrued Vested Participant or Spouse shall revert to the
         Employer in the event of termination of the Plan.


<PAGE>   15
                                                                              13


                                   ARTICLE XII

                            MISCELLANEOUS PROVISIONS

12.1     No Guarantee of Employment. Nothing contained herein shall be deemed to
         give any individual the right to be retained in the service of the
         Employer or to interfere with the rights of the Employer to discharge
         any individual at any time, with or without cause.

12.2     Non-Alienation of Benefits. No retirement benefit payable hereunder may
         be assigned, pledged, mortgaged or hypothecated and, to the extent
         permitted by law, no such retirement benefit shall be subject to legal
         process or attachment for the payment of any claims against any person
         entitled to receive the same. Notwithstanding any provision herein to
         the contrary, the Employer may, as the Compensation Committee in its
         sole and absolute discretion shall determine, offset any amount to be
         paid to a Participant, Accrued Vested Participant, or Spouse hereunder
         in order to recoup amounts that have been misappropriated by such
         Participant or Accrued Vested Participant or in order to reimburse
         amounts that have been advanced to such Participant or Accrued Vested
         Participant for expense accounts or similar circumstances and that
         remain outstanding upon termination of employment.

12.3     Payment to Incompetents. If a Participant or Accrued Vested Participant
         entitled to receive any retirement benefit payments hereunder is deemed
         by the Compensation Committee or is adjudged by a court of competent
         jurisdiction to be legally incapable of giving valid receipt and
         discharge for such retirement benefit, such payments shall be paid to
         such person or persons as the Compensation Committee shall designate or
         to the duly appointed guardian. Such payments shall, to the extent
         made, be deemed a complete discharge for such payments under this Plan.


<PAGE>   16
                                                                              14


12.4     Loss of Benefits. At the sole discretion of the Compensation Committee,
         and after written notice to the Participant, Accrued Vested
         Participant, or his Spouse as beneficiary, rights to receive any
         retirement benefit under this Plan may be forfeited, suspended, reduced
         or terminated in cases of gross misconduct by the Participant or
         Accrued Vested Participant which is reasonably deemed to be prejudicial
         to the interests of the Employer or a subsidiary of the Employer,
         including but not limited to the utilization or disclosure of
         confidential information for gain or otherwise.

12.5     Noncompetition. A Participant and Accrued Vested Participant shall
         forfeit for himself and his Spouse any and all retirement benefits
         pursuant to this Plan if said Participant or Accrued Vested Participant
         violates the notice provision of the next paragraph hereof or anywhere
         in the United States or outside of the United States, directly or
         indirectly, owns, manages, operates, joins or controls, or participates
         in the ownership, management, operation or control of, or becomes a
         director or an employee of, or a consultant to, any person, firm, or
         corporation which competes with the Employer; provided, however, that
         the provisions of this Article 12.5 shall not apply to investments by
         the Participant or Accrued Vested Participant in shares of stock traded
         on a national securities exchange or on the national over-the-counter
         market which shall have an aggregate market value, at the time of
         acquisition, of less than two (2%) percent of the outstanding shares of
         such stock.

         A Participant and Accrued Vested Participant shall be obligated to give
         the Employer at least sixty (60) days' prior written notice, registered
         or certified mail, postage prepaid, addressed to the Secretary, Hubbell
         Incorporated, 584 Derby Milford Road, Orange, Connecticut, 06477, of
         his intention, directly or indirectly, to own, manage, operate, join


<PAGE>   17
                                                                              15


         or control, or participate in the ownership, management, operation or
         control of, or become a director or an employee of, or a consultant to,
         any person, firm, or corporation, following which, within a period of
         sixty (60) days from its receipt of such notice, the Employer will mail
         to the Participant or Accrued Vested Participant by registered or
         certified mail, postage prepaid, a statement of its opinion as to
         whether said intention of the Participant or Accrued Vested Participant
         violates this Article 12.5.

12.6     Withholding. Payments made by the Employer under this Plan to any
         Participant, Accrued Vested Participant, or Spouse shall be subject to
         withholding as shall, at the time for such payment, be required under
         any income tax or other laws, whether of the United States or any other
         jurisdiction.

12.7     Expenses. All expenses and costs in connection with the operation of
         this Plan shall be borne by the Employer.

12.8     Governing Law. The provisions of this Plan will be construed according
         to the laws of the State of Connecticut, excluding the provisions of
         any such laws that would require the application of the laws of another
         jurisdiction.

12.9     Gender and Number. The masculine pronoun wherever used herein shall
         include the feminine gender and the feminine the masculine and the
         singular number as used herein shall include the plural and the plural
         the singular unless the context clearly indicates a different meaning.

12.10    Titles and Heading. The titles to articles and headings of sections of
         this Plan are for convenience of reference only and in case of any
         conflict, the text of the Plan, rather than such titles and headings,
         shall control.


<PAGE>   18
                                                                              16


                                  ARTICLE XIII

                                CHANGE OF CONTROL

13.1     The provisions of Section 13.3 shall become effective immediately upon
         the occurrence of a Change of Control (as defined in Section 13.2(a)).

13.2     (a)      "Change of Control" shall mean any one of the following:

                  (i)      Continuing Directors no longer constitute at least
                           2/3 of the Directors;

                  (ii)     any person or group of persons (as defined in Rule
                           13d-5 under the Securities Exchange Act of 1934),
                           together with its affiliates, becomes the beneficial
                           owner, directly or indirectly, of twenty (20%)
                           percent or more of the voting power of the then
                           outstanding securities of the Employer entitled to
                           vote for the election of the Employer's directors;
                           provided that this Article XIII shall not apply with
                           respect to any holding of securities by (A) the trust
                           under a Trust Indenture dated September 2, 1957 made
                           by Louie E. Roche, (B) the trust under a Trust
                           Indenture dated August 23, 1957 made by Harvey
                           Hubbell, and (C) any employee benefit plan (within
                           the meaning of Section 3(3) of the Employee
                           Retirement Income Security Act of 1974, as amended)
                           maintained by the Employer or any affiliate of the
                           Employer;

                  (iii)    the approval by the Employer's stockholders of the
                           merger or consolidation of the Employer with any
                           other corporation, the sale of substantially all of
                           the assets of the Employer or the liquidation or
                           dissolution of the Employer, unless, in the case of a
                           merger or consolidation, the incumbent Directors in
                           office immediately prior to such


<PAGE>   19
                                                                              17


                           merger or consolidation will constitute at least 2/3
                           of the Directors of the surviving corporation of such
                           merger or consolidation and any parent (as such term
                           is defined in Rule 12b-2 under the Securities
                           Exchange Act of 1934) of such corporation; or

                  (iv)     at least 2/3 of the incumbent Directors in office
                           immediately prior to any other action proposed to be
                           taken by the Employer's stockholders determine that
                           such proposed action, if taken, would constitute a
                           change of control of the Employer and such action is
                           taken.

         (b)      "Continuing Director" shall mean any individual who is a
                  member of the Employer's Board of Directors on December 9,
                  1986 or was designated (before such person's initial election
                  as a Director) as a Continuing Director by 2/3 of the then
                  Continuing Directors.

         (c)      "Director" shall mean any individual who is a member of the
                  Employer's Board of Directors on the date the action in
                  question was taken.

         (d)      "Change of Control Transaction" shall mean the closing of the
                  transaction constituting the Change of Control, which shall
                  include, for purposes of the events described in Section
                  13.2(a)(iii), above, the consummation of the merger or
                  consolidation approved by Hubbell's stockholders.

13.3     (a)      Section 2.10 is deleted and the following is inserted in lieu
                  thereof:

                           "Key Executive" means (a) (i) any Officer elected
                           prior to May 1, 1993 and (ii) any other Employee who
                           was so designated by the Compensation Committee prior
                           to May 1, 1993, and (b) any Officer or other Employee

<PAGE>   20
                                                                              18


                           who is so designated by the Compensation Committee on
                           or after May 1, 1993."

         (b)      Section 2.18 is deleted and the following is inserted in lieu
                  thereof:

                           "Totally and Permanently Disabled" shall mean, with
                           reference to a Participant hereunder, that as a
                           result of bodily or mental injury or disease, whether
                           occupational or non-occupational in origin, as
                           determined by competent medical authority selected by
                           the Participant or by such Participant's
                           representative, he is wholly and permanently
                           prevented from engaging for remuneration or profit in
                           any occupation or employment for which he is
                           reasonably suited by education, training and
                           experience.

         (c)      The remainder of Section 5.2 is deleted after "attains age
                  65)" on the seventh and eighth lines of page 5.

         (d)      The remainder of Section 5.4 is deleted after "date of his
                  termination of employment" on the ninth and tenth lines in
                  Section 5.4 on page 6.

         (e)      The following is added to the end of Section 6.1(a):

                  "Notwithstanding any of the foregoing, unless otherwise
                  provided in an agreement between a Participant and the
                  Employer with respect to any benefit provided for herein,
                  upon the occurrence of a Change of Control Transaction,
                  unless a Participant (whether current or former) elects
                  otherwise during the period of ten days after the signing of
                  any agreement by the Company that would, upon the
                  consummation of the transactions contemplated therein, result
                  in a Change of Control, all amounts otherwise payable
                  pursuant to the schedules set forth in Section 6.1(a) and (b)
                  hereof, shall be paid out in one lump sum no later than ten
                  days after a Participant's termination of employment



<PAGE>   21
                                                                              19


                  with the Employer. The amounts to be paid out in such lump sum
                  shall be calculated using the actuarial assumptions set forth
                  on Exhibit A, attached hereto."

         (f)      In the first sentence of Section 7.1, the phrase "If a
                  Participant is deemed by the Compensation Committee to have
                  incurred a Total Disability" is deleted and in lieu thereof is
                  inserted the phrase "If a Participant becomes Totally and
                  Permanently Disabled". Section 7.2 is deleted.

         (g)      Section 10.1 is deleted and the following is inserted in lieu
                  thereof:

                           "The Plan shall be administered by the Compensation
                           Committee which shall have full authority to
                           interpret the Plan, to establish rules and
                           regulations relating to the Plan, to determine the
                           criteria for eligibility to participate in the Plan,
                           to select Participants in the Plan, and to make all
                           other determinations and take all other actions
                           necessary or appropriate for the proper
                           administration of the Plan. No member of the
                           Compensation Committee shall be eligible to
                           participate in the Plan."

         (h)      The remainder of Section 12.2 is deleted beginning with
                  "Notwithstanding any provision herein" on the fourth and fifth
                  lines of Section 12.2 on page 13.

         (i)      In Section 12.3, all references to "Compensation Committee"
                  are deleted and in lieu thereof is inserted the term
                  "Trustee".

         (j)      Section 12.4 is deleted.

         (k)      Section 12.5 is deleted.

         (l)      New Section 12.11 is inserted as follows:


<PAGE>   22
                                                                              20


                  "Notwithstanding any other provisions of the Plan to the
                  contrary:

                  (i)      the accrued benefit hereunder of any Participant as
                           of the date of a Change of Control may not be
                           reduced;

                  (ii)     any Service accrued by a Participant as of the date
                           of a Change of Control cannot be reduced;

                  (iii)    no amendment or action of the Compensation Committee
                           which affects any Participant is valid and
                           enforceable without the prior written consent of such
                           Participant; and

                  (iv)     no termination of the Plan shall have the effect of
                           reducing any benefits accrued under the Plan prior to
                           such termination."

Adopted by the Board of Directors on March 11, 1980 and amended on September 1,
1984, December 9, 1986, December 19, 1990, December 18, 1991, December 16, 1992,
May 1, 1993, December 11, 1996, December 10, 1997, and December 8, 1999.







<PAGE>   23
                                                                              21


                                    EXHIBIT A

                                   ASSUMPTIONS

The assumptions to be used are those specified under Section 417(e) of the
Internal Revenue Code of 186, as amended, which assumptions are the minimum lump
sum factors permitted to be used for calculating pension benefits under
qualified defined benefit plans.

Benefit:          Lump sum payment of unreduced benefit deferred to age 55,
                  increased to reflect the 50% joint and survivor form.

Mortality Rates:  The 1983 Group Annuity Mortality (1983 GAM) blend of 50% male
                  and 50% female rates.

Interest Rate:    10-year treasury rate on the first day of the fourth quarter
                  of the calendar year immediately prior to the date on which
                  the Participant retires or otherwise separates from Service.

Other:            3% annual Social Security wage base increase.
                  2.5% annual CPI increase.
                  5% annual salary increase.

Qualified Plan
Offset:           Amount actually payable at age 55 (or, if higher, the
                  participants actual age as of the date of termination of
                  employment).