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                                                                    EXHIBIT 10.3

                                NEN HOLDING INC.
                                549 Albany Street
                           Boston, Massachusetts 02118

July 10, 1997


Mr. George Uveges
26042 Tallwood Drive
North Olmsted, Ohio 44070-2706


Dear George:

This letter extends an offer to you to become the Vice President for
Administration and Chief Financial Officer of NEN Holding Inc. and NEN Life
Science Products, Inc. ("NEN" or the "Company"). After your efforts as our
consultant for the past several months, it is clear that you bring the scope,
talent and experience necessary to lead the financial functions of our company
in the years ahead. Please consider this document a conveyance of the basic
terms and agreements of our offer.

POSITION RESPONSIBILITY

You shall serve as Vice President for Administration and Chief Financial Officer
for developing, implementing, and maintaining the financial systems of NEN,
which include worldwide controller, financial analysis and reporting, and
treasury functions. Further, you will coordinate the development of strategic,
long range operating and annual budget plans, as well as the evaluation of
acquisition and divestiture opportunities. Also, you will direct the development
and implementation of our global information systems to support NEN as a stand
alone company.

Your official start date of these duties will be July 7, 1997.

SALARY

The minimum base salary of your position will be $170,000 per annum, which shall
be paid in installments on a bi-weekly basis. The Company shall review your
performance on each anniversary of your date of hire and at its sole discretion
may increase your base salary for the position based on your performance and the
financial condition of the Company at that time.

BONUS AND INCENTIVE COMPENSATION

A copy of the draft executive bonus plan entitled "Annual Incentive Plan" will
be faxed to you in the next few days and I will be pleased to review it with
you. Central to that discussion will be the Company's budgeted EBITDA, a
performance measurement on which the incentive plan is based. In 1997, the
EBITDA budget is approximately $25.0 million. Typically, the design of our plans
contains the following key elements:


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Mr. George Uveges
July 10, 1997
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     (1)  threshold for payment of any bonuses is corporate performance of 85%
          of the EBITDA budget.

     (2)  target bonuses are paid upon achieving 110% of the EBITDA budget.

     (3)  bonuses are not capped.

     (4)  the plan incorporates an increasing percentage of payout as Company
          performance progresses from threshold to budget to 110% of budget and
          beyond.

     (5)  at threshold, your bonus would be approximately 10% of salary and at
          110% of budget, your bonus would be 40% of salary.

     (6)  the bonus for each individual will be split between corporate
          performance and personal objectives, with the greatest weight given to
          corporate performance.

Your minimum guaranteed bonus for your first full year of employment will be
$25,000. If your performance and payout as measured by the annual incentive plan
exceeds the guaranteed amount, you will receive the higher of the two figures
for your payout. Since the bonus plan will be based on earnings for a full
fiscal year, five-twelfth (5/12) of the $25,000 guarantee to be applicable to
1997 and seven-twelfth (7/12) applicable to 1998.

EQUITY PARTICIPATION

You have been invited to co-invest with myself and Genstar Capital Partners II,
L.P. ("Genstar") in NEN. We offer you the opportunity to invest up to $150,000
in the Company. Your investment will be made at the same price that I and
Genstar paid at the time of the transaction and we will enter into a
Stockholders' Agreement outlining the rights and responsibilities of the
shareholders. All shareholders will be subject to dilution for such things as
the proposed stock option plan.

STOCK OPTION

The Board of Directors of NEN will establish a Stock Option Plan setting aside
ten percent (10%) of the stock of the Company on a fully diluted basis.
Coincident with your employment, the Company will grant you an option to buy 250
shares at a grant price of $100 per share. The plan has a ten (10) year life and
a five (5) year vesting schedule in equal twenty percent (20%) increments on
each anniversary date of the grant. Further grants of stock options to you would
normally be made annually at the Board's discretion based upon your and the
Company's performance.

Should there be a significant change whereby Genstar's nominees no longer
control the Board of Directors ("Change of Control") and you are subsequently
terminated without Cause (see "Severance Agreement" below for definition of
Cause) by the Board of Directors, or you


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Mr. George Uveges
July 10, 1997
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terminate with good reason, within eighteen (18) months of the Change of
Control, all stock options that have been granted to you will vest immediately.

BENEFITS

You shall be entitled to participate in the Company's benefit plans, including
group health and medical insurance plans, as they are adopted from time to time
beginning on the first day of the following your employment. Description of
these plans will be sent under separate cover and someone will be available to
provide further explanation. You shall be entitled to four (4) weeks paid
vacation per year.

PENSION AND 401K SAVINGS PLAN

You will be eligible to join the pension plan and 401K savings plan of NEN. Both
of these plans are similar to those provided to the employees of NEN by DuPont.
NEN has contractually agreed with DuPont to maintain a benefits package
"substantially similar" to the current DuPont benefits package for a period of
three (3) years from the date of closing.

SEVERANCE AGREEMENT

NEN will provide protection for you in the event of your termination for reasons
other than Cause. If you are terminated without Cause or if you resign for good
reason, you will receive one (1) year's base salary and eighteen (18) months
continuation of benefits. Attached as Schedule A is a definition of Cause and
Resignation without Good Reason.

EXPENSE REIMBURSEMENT

The Company will reimburse you for reasonable and necessary business expenses
incurred while performing your duties as described in this letter, subject to
the policies, procedures and controls that the Company may from time to time
adopt. Expense reimbursement will be subject to the approval of the CEO. The
Company will pay your relocation expenses according to policy. If, in addition,
NEN fails to perform according to our agreement, NEN will reimburse you for your
legal fees and expenses in connection with resolution of the dispute.

SUCCESSORS: BINDING AGREEMENT

This agreement shall not be terminated by any merger or consolidation of the
transfer of all or substantially all of the assets of NEN. In the event of such
transaction, the provisions of this agreement shall be binding on the surviving
entity. NEN will cause any successor to assume all of the obligations of the
agreement. Failure to obtain such assumption prior to the effective date of the
merger or consolidation shall constitute Good Reason hereunder and entitle you
to terminate your employment and receive the compensation and benefits as
contained in this agreement.


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Mr. George Uveges
July 10, 1997
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If you should die while any amounts payable to you were owing had you continued
to live, those amounts will be payable to such persons as you appoint in
writing, or if no such persons are appointed, to your estate.

INDEMNIFICATION

The Company will indemnify you to the fullest extent permitted by law for any
liability incurred as a result of the conduct of your duties as an officer of
NEN.

George, I believe that NEN will provide an excellent opportunity for your next
challenge. I am extending this offer to you to become our Vice President for
Administration and Chief Financial Officer in good faith, and I look forward to
a long and close working relationship with you.

Sincerely,

/s/ John L. Zabriskie
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John L. Zabriskie
Chairman, President and Chief Executive Officer

Attachment


Accepted this 10th day of July, 1997.

/s/ George Uveges
------------------------------------
George Uveges


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                                                                      SCHEDULE A

          SECTION 1. Termination of Employment. (a) Termination for Cause;
Resignation Without Good Reason. (i) If the Executive's employment is terminated
by the Company for Cause (as defined below), or if the Executive resigns from
his employment hereunder, other than for Good Reason (as defined below), the
Executive shall be entitled to only (A) severance benefits as provided by the
Company's general procedures and practices applicable to all employees
terminated in like circumstances, if any, and (B) payment of the pro rata
portion of the Executive's salary through and including the date of termination
or resignation.

          (ii) For purpose of this Agreement, termination for "Cause" shall mean
termination of the Executive's employment by the company because of (A) the
Executive's conviction for, or guilty plea to, a felony or a crime involving
moral turpitude; (B) the Executive's commission of an act of willful gross
misconduct resulting in material harm to the Company; or (C) the Executive's
willful and repeated failure, after written notice, to follow the written
policies of the Company as established by the board of the directors of the
Company ("the Board").

          (iii) For purposes of this Agreement, resignation for "Good Reason"
shall mean the resignation of the Executive after (A) notice in writing is given
to him of his relocation, without the Executive's consent, to a place of
business more than 35 miles outside of the Boston Metropolitan Statistical Area,
(B) a reduction in the Executive's benefits or pay or (C) a substantial adverse
alteration occurs in the nature or status of the Executive's responsibilities
from those in effect on the date hereof.

          (iv) The date of termination for Cause shall be the date of receipt by
the Executive of written notice of such termination. The date of resignation
without Good Reason shall be the date of receipt by the Company of a written
notice of such resignation.