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                                                                     Exhibit 4.2

                                                                      Final Plan
                                                             last revised 1/5/99

                                HADCO CORPORATION
                         NON-QUALIFIED STOCK OPTION PLAN
                                NOVEMBER 29, 1995
                      AS AMENDED AND RESTATED JULY 1, 1998

             1. PURPOSE. This Non-Qualified Stock Option Plan (hereinafter, the
"Plan") is intended to promote the interests of Hadco Corporation (hereinafter,
the "Company") by providing an inducement for highly qualified personnel to
enter the employ of the Company and an incentive for valued employees to remain
with the Company and to use their best efforts to promote the Company's
continued success, by means of the offer of an opportunity to acquire or
increase their proprietary interest in the Company through the granting of
options to purchase the Company's stock pursuant to the terms of this Plan. As
used herein, the term "Company" includes any present or future subsidiary and
any successor corporation.

             2. RIGHTS TO BE GRANTED. Under this Plan, options may be granted
that give an optionee the right for a specified time period to purchase a
specified number of shares of common stock, par value $0.05, of the Company. The
option price shall be determined in each instance by the Stock Option Committee,
in accordance with the terms of this Plan, including, without limitation, under
Section 7 hereof.


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             3. AVAILABLE SHARES. The total number of shares of common stock,
par value $0.05, of the Company, for which options may be granted shall be One
Million (1,000,000) shares, subject to adjustment in accordance with Paragraph
11 of this Plan. Shares subject to the Plan may be either authorized but
unissued shares or shares that were once issued and subsequently reacquired by
the Company. If any options granted under this Plan are surrendered before
exercise or lapse without exercise, in whole or in part, the shares reserved
therefor shall revert to the option pool and shall continue to be available
under the Plan. No one employee of the Company may be granted options to
acquire, in the aggregate, more than 300,000 shares of Common Stock under this
Plan. If any option granted under this Plan shall expire or terminate for any
reason without having been exercised in full or shall cease for any reason to be
exercisable in whole or in part or shall be repurchased by the Company, the
shares subject to such option shall be included in the determination of the
aggregate number of shares of common stock deemed to have been granted to such
employee under this Plan.

             4. ADMINISTRATION. The Plan shall be administered by the Stock
Option Committee (hereinafter, the "Committee"), which shall consist of two or
more members appointed by the Board of Directors of the Company; provided,
however that the Plan shall be administered: (I) to the extent required by
applicable regulations under Section 162(m) of the Internal Revenue Code of
1986, by two or more "outside directors" (as defined in applicable regulations
thereunder) and (ii) to the extent


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required by Rule 16b-3 promulgated under the Securities Exchange Act of 1934 or
any successor provision ("Rule 16b-3"), by a disinterested administrator or
administrators within the meaning of Rule 16b-3. The Board may at any time and
from time to time thereafter appoint additional or substitute members of the
Committee and may fill vacancies on the Committee, however caused. No person
shall be a member of the Committee who is not a Director of the Company.

                   In the event no Committee is appointed, the Board shall act
as the Committee and all references in this Plan to the Committee shall mean the
Board. If a Committee is appointed but under applicable law does not have
authority to undertake any duty stated herein, the Board shall act as and for
the Committee for the purpose of undertaking that particular duty.

                   The Committee shall choose one of its members as Chair and
shall hold meetings at such times and places as it deems advisable. A majority
of the members of the Committee shall constitute a quorum, and any action may be
taken by a majority of those present and voting at any meeting.

                   Subject to the provisions of this Plan, the Committee shall
have authority in its discretion to determine the employees of the Company to
whom options shall be granted, the number of shares to be covered by each
option, the time or times at which options shall be granted, the purchase price
of the stock covered by each option, the time or times during the term of option
(defined in Section 9) at which each such option shall become exercisable, the
form of agreement to be used in granting


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the options, and shall further have the authority to interpret this Plan, and to
prescribe, amend and rescind rules and regulations relating to it. All questions
of interpretation and application of this Plan and of any options issued under
it shall be determined by the Committee, and such determination shall be final
and binding upon all persons.

                   No member of the Board or of the Committee shall be liable
for any action or determination made in good faith with respect to the Plan or
any option granted under it.

             5. GRANT OF OPTIONS. The Committee may from time to time grant
options to eligible persons pursuant to the provisions of this Plan. Each
option so granted shall be evidenced by an Option Agreement, in such form as may
be approved by the Committee, which Agreement shall be duly executed and
delivered on behalf of the Company and by the optionee to whom such option is
granted. The Agreement may contain such terms, provisions, and conditions not
inconsistent with the Plan as may be determined by the Committee, including
restrictions to be imposed on the shares acquired by a participant upon the
exercise of an option granted to him.

                   The grant of an option under this Plan shall be effective as
of the date of the vote of the Stock Option Committee of the Board of
Directors of the Company to issue such an option. The granting of options under
this Plan shall be entirely discretionary and nothing in this Plan shall be
deemed to give any employee any right to participate in this Plan or to receive
options.


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                   The grant of an option under this Plan confers no right upon
the optionee with respect to the continuation of his employment with the Company
or a subsidiary of the Company. Nothing contained in this Plan or any option
agreement issued hereunder shall be construed as interfering with or restricting
the right of the Company or its subsidiary or the optionee to terminate his
employment at any time.

             6. ELIGIBILITY AND LIMITATIONS. Options may be granted pursuant to
this Plan only to employees of the Company or of any present or future
subsidiary corporation; provided, however, that a person shall be considered to
be an employee within the meaning of this Plan if the person has executed a
written employment agreement with the Company which provides for the start of
active employment within one (1) month of the date of grant of an option. In
determining the eligibility of an individual to be granted an option, as well as
in determining- the number of shares to be optioned to any individual, the
Committee shall consider the responsibilities of the person being considered,
the nature and value to the Company or its subsidiaries of his service and
accomplishments, his present and potential contribution to the success of the
Company or its subsidiaries, and such other factors as the Committee may deem
relevant.

                   No option may be granted under this Plan after December 31,
2005.

             7. OPTION PRICE. The purchase price of the stock covered by an
option granted pursuant to this Plan shall be the


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fair market value of the underlying shares of Common Stock on the date the
option is granted.

                   If the Company's common stock is actively traded in the
established over-the-counter market, the fair market value of such common stock
shall be the mean between the bid and asked prices quoted in such
over-the-counter market at the close on the date nearest preceding the date of
grant. If such common stock is listed on any national exchange, or traded in the
Nasdaq National Market, the mean between the high and low sale prices quoted on
such exchange or market on the trading day nearest preceding the date of the
granting of the option may be taken as such fair market value. If the stock is
not publicly traded, the fair market value shall be determined from time to time
by the Board of Directors.

                   The full purchase price per share (determined after any
appropriate adjustment has been made under the terms of Section 11 of this Plan)
shall be paid as provided in Section 8 below.

             8. EXERCISE OF OPTION. Subject to the terms and conditions of this
Plan and the Option Agreement, an option granted hereunder shall be exercisable
in whole or in part by giving written notice to the Company by mail or in person
addressed to Treasurer, Hadco Corporation, 12A Manor Parkway, Salem, New
Hampshire 03079, stating the number of shares with respect to which the option
is being exercised, accompanied by payment in full for such shares, which
payment may be made (a) in United States dollars in cash or by check, or (b) at
the


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discretion of the Committee, through delivery of shares of Common Stock having a
fair market value equal as of the date of the exercise to the cash exercise
price of the option, or (c) at the discretion of the Committee and consistent
with applicable law, through the delivery of an assignment to the Company of a
sufficient amount of the proceeds from the sale of the Common Stock acquired
upon exercise of the option and an authorization to the broker or selling agent
to pay that amount to the Company, which sale shall be at the participant's
direction at the time of exercise, or (d) at the discretion of the Committee, by
any combination of (a), (b) and (c) above. There shall be no such exercise at
any one time as to fewer than one hundred (100) shares or all of the shares then
purchasable by the person or persons exercising the option, if fewer than one
hundred (100) shares. A copy of such notice shall be provided to Hamilton &
Dahmen, LLP, 73 Tremont Street, Boston, Massachusetts 02108, or to such other
counsel as the Company may hereafter designate, and to the Bank of Boston,
Shareholder Services Division, Post Office Box 644, Boston, Massachusetts 02102,
or to such other Stock Transfer Agent as the Company may hereafter designate.
The Transfer Agent shall, on behalf of the Company, prepare a certificate or
certificates representing such shares acquired pursuant to exercise of the
option, shall register the optionee as the owner of such shares on the books of
the Company and shall cause the fully executed certificate(s) representing such
shares to be delivered to the optionee as soon as practicable after payment of
the option price in full. The holder of an option


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shall not have any rights of a shareholder with respect to the shares covered by
the option, except to the extent that one or more certificates for such shares
shall be delivered to him upon the due exercise of the option.

             9. TERM AND TRANSFERABILITY OF OPTIONS.

             (a) Each option shall become exercisable as provided in each option
granted by the Company to the participant and as provided in each respective
Option Agreement, but in no event shall the option be exercisable during a
period longer than the period beginning with the date of grant and ending not
later than ten (10) years from such date of grant.

             (b) Any option granted pursuant to this Plan shall not be
assignable or transferable except by will or by the laws of descent and
distribution. During the lifetime of the optionee, any option shall be
exercisable only by the optionee to whom the option is granted. Any option
granted hereunder shall be null and void and without effect upon the bankruptcy
of the optionee to whom the option is granted, or upon any attempted assignment
or transfer, including without limitation, any purported assignment, whether
voluntary or by operation of law, pledge, hypothecation or other disposition,
attachment, trustee process or similar process, whether legal or equitable, upon
such option.

             10. TERMINATION OF OPTION RIGHTS.

         (a) In the event an optionee ceases to be an employee of the Company
for any reason other than death, retirement from the Company on or after normal
retirement age as described in the Hadco Corporation Retirement Plan, as it may
be amended from time


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to time, or any successor Plan (or retirement on or after such other earlier age
as may be permitted in the individual option agreement between the optionee and
the Company) or disability, any unvested or unexercised options granted to such
optionee shall terminate and become void at midnight on the thirtieth (30) day
after the date of termination, but in no event later than the specified
expiration date of the option.

             (b) In the event that an optionee ceases to be an employee of the
Company by reason of his or her disability or death, any option granted to such
optionee shall be immediately and automatically accelerated and all previously
unexercised options (to the extent that they have not previously been forfeited
in accordance with the terms of the individual option agreement) shall vest and
be exercisable (by the optionee's personal representative, heir or legatee, in
the event of death) during the period ending one hundred eighty (180) days after
the date of termination of employment, but in no event later than the specified
expiration date of the option.

         (c) In the event an optionee ceases to be an employee of the Company by
reason of his or her retirement on or after normal retirement age as described
in the Hadco Corporation Retirement Plan, as it may be amended from time to
time, or any successor Plan (or retirement on or after such other earlier age as
may be permitted in the individual option agreement between the optionee and the
Company), any option granted to such employee which had vested as of the date of
retirement may be exercised during the period ending ninety (90) days after the
date of retirement;


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provided, however, that an individual option agreement may provide different
rights to a retiring optionee than those contained in this section 10(c); and
provided further that in no event may any option be exercisable later than the
specified expiration date of the option.

             (d) For purposes of the Plan, a transfer of an employee between the
parent Company and a subsidiary company, or between subsidiary companies, shall
not be deemed a termination of employment.

             11. ADJUSTMENTS UPON CHANGES IN CAPITALIZATION.

             (a) In the event that the outstanding shares of the Common Stock of
the Company are changed into or exchanged for a different number or kind of
shares or other securities of the Company by reason of any reorganization,
recapitalization, reclassification, stock split-up, combination of shares or
dividends payable in capital stock, appropriate adjustments shall be made in the
number and kind of shares as to which options may be granted under the Plan and
as to which outstanding options or portions thereof then unexercised shall be
exercisable, to the end that the proportionate interest of the option holder
shall be maintained as before the occurrence of such event. Such adjustment in
outstanding options shall be made without change in the total price applicable
to the unexercised portion of such options and with a corresponding adjustment
in the option price per share.

             (b) Upon any sale of all or substantially all of the assets of the
Company, or upon any merger, consolidation or


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tender offer in respect of which the stockholders holding all of the Company's
outstanding voting securities immediately prior to the consummation thereof hold
less than 50% of all of the Company's outstanding voting securities immediately
after such consummation (each of the foregoing sale, merger, consolidation or
tender offer hereinafter called an "Acquisition"), then the date upon which all
then outstanding options granted under this Plan become fully vested and
exercisable shall be automatically accelerated to occur immediately prior to the
consummation of such Acquisition; provided, however, that any such then
outstanding options which are not thereupon exercised in full immediately prior
to the consummation of such Acquisition shall thereupon terminate.

             (c) In the event of a recapitalization or reorganization of the
Company (other than a transaction described in subsections 11(a) and (b) above)
pursuant to which securities of the Company or of another corporation are issued
with respect to the outstanding shares of Common Stock, an optionee upon
exercising an option shall be entitled to receive for the purchase price paid
upon such exercise securities he or she would have received if he or she had
exercised such option prior to such recapitalization or reorganization. In the
event of the proposed dissolution or liquidation of the Company, each option
will terminate immediately prior to the consummation of such proposed action or
at such other time and subject to such other conditions as shall be determined
by the Committee. Except as expressly provided herein, no issuance by the
Company of shares of stock of


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any class, or securities convertible into shares of stock of any class, shall
affect, and no adjustment by reason thereof shall be made with respect to, the
number or price of shares subject to options. No adjustments shall be made for
dividends paid in cash or in property other than securities of the Company. No
fractional shares shall be issued under the Plan and the optionee shall receive
from the Company cash in lieu of such fractional shares. Upon the happening of
any of the events described in this Section 11, the class and aggregate numbers
of shares set forth in Section 3 hereof that are subject to options which
previously have been or subsequently may be granted under this Plan, as well as
the 300,000 figure in Section 3, shall also be appropriately adjusted to reflect
the events described in such subparagraphs. The Committee or the Successor Board
shall determine the specific adjustments to be made under this Section 11 and,
subject to Section 2, its determination shall be conclusive.

             12. RESTRICTIONS ON ISSUANCE OF SHARES.

Notwithstanding the provisions of Section 8 of the Plan, the Company shall have
no obligation to deliver any certificate or certificates upon exercise of an
option until one of the following conditions shall be satisfied:

                       (i) The shares with respect to which the option has been
             exercised are at the time of the issue of such shares effectively
             registered under applicable Federal and State securities acts as
             now in force or hereafter amended; or


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                       (ii) Counsel for the Company shall have given an opinion
             that such shares are exempt from registration under Federal and
             State securities acts as now in force or hereafter amended; and
             until the Company has complied with all applicable laws and
             regulations, including without limitation all regulations required
             by any stock exchange upon which the Company's outstanding common
             stock is then listed.

                       The Company shall use its best efforts to bring about
compliance with the above conditions within a reasonable time, except that the
Company shall be under no obligation to cause a registration statement or a
post-effective amendment to any registration statement to be prepared at its
expense solely for the purpose of covering the issue of shares in respect of
which any option may be exercised.

                       Any stock purchased under the Plan prior to shareholder
approval of the Plan may not be sold, assigned, transferred, pledged or
encumbered in any way and will be held in escrow by the Company until
shareholder approval for the Plan is obtained, and if such approval is not
obtained by the earlier of (i) the next annual meeting of stockholders of the
Company, or (ii) June 30, 1996, the purchase of such stock and any option
granted hereunder and this Plan will be automatically- rescinded and the
purchase price returned to purchasing optionees without interest.

             13. REPRESENTATIONS OF OPTIONEE. The Company may require the
optionee to deliver such written warranties and


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representations upon exercise of the option that the Company deems reasonable or
necessary, including without limitation a representation that a purchase of
shares under the option is made for investment and not with a view to their
distribution (as that term is used in the Securities Act of 1933).

             14. MODIFICATION OF OUTSTANDING OPTIONS. The Committee or the
Board of Directors may accelerate the exercisability of any outstanding option
and may authorize changes to any outstanding option with the consent of the
participant (including, without limitation, to extend the term of an option upon
termination of employment to a date not later than ten (10) years from the
original grant date) when and subject to such conditions as are deemed to be in
the best interests of the Company and in accordance with the purposes of the
Plan.

             15. APPROVAL OF STOCKHOLDERS. The Plan shall be subject to approval
by the affirmative vote of stockholders holding at least a majority of the
voting stock of the Company voting in person or by proxy at or by the earlier of
(i) the next annual meeting of stockholders of the Company, or (ii) June 30,
1996, and the Plan shall take effect as of the date of adoption immediately upon
such approval.

             16. TERMINATION AND AMENDMENT OF PLAN. The Plan shall expire at the
end of the business day on December 31, 2005 (except as to options outstanding
on that date). The Board may at any time terminate the Plan or make such
modification or amendment thereof as it deems advisable; provided, however, that
except as provided in Section 11 the Board may not, without


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approval of the stockholders of the Company obtained in the manner stated in
Section 15 (without regard to clauses (i) and (ii) therein), increase the
maximum number of shares for which options may be granted under the Plan. To the
extent required by Rule 16b-3, any other amendments to this Plan shall be
approved by the stockholders of the Company in the manner stated in Section 15
(without regard to clauses (i) and (ii) therein). Termination or any
modification or amendment of the Plan shall not, without consent of a
participant, affect his rights under an option previously granted to him.

             17. WITHHOLDING OF ADDITIONAL INCOME TAXES. Upon any exercise of
any option or the vesting or transfer of restricted stock or securities acquired
on the exercise of an option hereunder, or the making of a distribution or other
payment with respect to such stock or securities, the Company may withhold taxes
in respect of amounts that constitute compensation includable in gross income.
The Committee in its discretion may condition (i) the exercise of an option, or
(ii) the vesting or transferability of restricted stock or securities acquired
by exercising an option, on the optionee's making satisfactory arrangement for
such withholding. Such arrangement may include payment by the optionee in cash
or by check of the amount of the withholding taxes or, at the discretion of the
Committee, by the optionee's delivery of previously held shares of Common Stock
or the withholding of shares from the shares of Common Stock otherwise
deliverable upon exercise of an option, with such


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shares in each case having an aggregate fair market value equal to the amount of
such withholding taxes.