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CREDIT SUISSE FIRST BOSTON LOGO
                                          CREDIT SUISSE FIRST BOSTON CORPORATION
 
                                          227 West Monroe Street
                                                          Telephone 312 750 3000
                                          Chicago, IL 60606-5018
 
                                                                         ANNEX A
 
Board of Directors
Hein-Werner Corporation
2210 Pewaukee Road
Waukesha, Wisconsin 53188
 
April 27, 1998
 
Dear Sirs:
 
     You have asked us to advise you with respect to the fairness to the
stockholders of Hein-Werner Corporation (the "Company") from a financial point
of view of the consideration to be received by such stockholders pursuant to the
terms of the draft Agreement and Plan of Merger, dated as of April 26, 1998 (the
"Merger Agreement"), among the Company, Snap-on Incorporated (the "Parent") and
Snap-on Pace Company (the "Purchaser"). The Merger Agreement provides for the
commencement by the Purchaser of a tender offer (the "Offer") to purchase all of
the issued and outstanding shares of common stock of the Company, par value
$1.00 per share, together with associated rights (together, the "Shares"), at a
price per Share of $12.60, net to the seller in cash, followed by a merger (the
"Merger") of the Purchaser with and into the Company pursuant to which the
Company will become a wholly owned subsidiary of the Parent, with each remaining
outstanding Share to be converted into the right to receive $12.60 in cash. The
Company has also granted an irrevocable option (the "Option") to the Purchaser
to acquire that number of Shares, at a price of $12.60 per share, required to
control 90% of the fully diluted Shares outstanding (assuming the issuance of
the Shares pursuant to the Option), provided that the Purchaser has accepted for
payment pursuant to the Offer at least 66 2/3% but less than 90% of the Shares
outstanding prior to the exercise of the Option.
 
     In arriving at our opinion, we have reviewed certain publicly available
business and financial information relating to the Company, as well as the
Merger Agreement and the draft Stock Option Agreement, dated as of April 26,
1998. We have also reviewed certain other information, including financial
forecasts, provided to us by the Company and have met with the Company's
management to discuss the business and prospects of the Company.
 
     We have also considered certain financial and stock market data of the
Company, and we have compared those data with similar data for other publicly
held companies in businesses similar to the Company and we have considered the
financial terms of certain other business combinations and other transactions
which have recently been effected. We also considered such other information,
financial studies, analyses and investigations and financial, economic and
market criteria which we deemed relevant.
 
     In connection with our review, we have not assumed any responsibility for
independent verification of any of the foregoing information and have relied on
its being complete and accurate in all material respects. With respect to the
financial forecasts, we have assumed that they have been reasonably prepared on
bases reflecting the best currently available estimates and judgments of the
Company's management as to the future financial performance of the Company. In
addition, we have not been requested to make, and have not made, an independent
evaluation or appraisal of the assets or liabilities (contingent or otherwise)
of the Company, nor have we been furnished with any such evaluations or
appraisals. Our opinion is necessarily based upon financial, economic, market
and other conditions as they exist and can be evaluated on the date hereof. In
connection with our engagement, we approached a limited number of third parties,
after approval by the Company, to solicit indications of interest in a possible
acquisition of the Company and held preliminary discussions with certain of
these parties prior to the date hereof.
 
     We have acted as financial advisor to the Company in connection with the
Merger and will receive a fee for our services, a significant portion of which
is contingent upon the consummation of the Merger.
 
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     In the ordinary course of our business, we and our affiliates may actively
trade the debt and equity securities of both the Company and the Parent for our
and such affiliates' own accounts and for the accounts of customers and,
accordingly, may at any time hold a long or short position in such securities.
 
     It is understood that this letter is for the information of the Board of
Directors in connection with its consideration of the Offer and the Merger, and
does not constitute a recommendation to any stockholder as to whether or not
such stockholder should tender shares pursuant to the Offer or vote in favor of
the Merger and is not to be quoted or referred to, in whole or in part, in any
registration statement, prospectus or proxy statement, or in any other document
used in connection with the offering or sale of securities, nor shall this
letter be used for any other purposes, without our prior written consent.
 
     Based upon and subject to the foregoing, it is our opinion that, as of the
date hereof, the consideration to be received by the stockholders of the Company
in the Offer and the Merger is fair to such stockholders from a financial point
of view.
 
Very truly yours,
 
CREDIT SUISSE FIRST BOSTON CORPORATION
 
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