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                                    SHC CORP.
                             390 SOUTH EIGHTH STREET
                                    2ND FLOOR
                           WEST DUNDEE, ILLINOIS 60118
          -------------------------------------------------------------


June 17, 1999


Terrence Donati
c/o SHC Corp.
390 South Eighth Street
2nd Floor
West Dundee, IL 60118

Dear Mr. Donati:

         Reference is herein made to that certain Promissory Note dated June 18,
1998 made by Fleetmax Corp. ("Fleetmax") and Marvin Koenig (collectively, the
"Maker") payable to the order of Sonoma Holding Corp. (together with its
subsidiaries and affiliates, the "Company") in the original principal amount of
$1,146,133 (the "Fleetmax Note"). This letter is intended to memorialize the
agreement of the parties with respect to settlement of all obligations and
liabilities related to the Fleetmax Note, which agreement is as follows:

         1.       The parties acknowledge and agree that the amounts due the
Company pursuant to the Fleetmax Note as of the date hereof are as set forth on
EXHIBIT A and that no other amounts are due the Company under or in connection
with the Fleetmax Note.

         2.       In order to effect realization of the note receiveable carried
on the books of the Company, upon execution of this letter agreement (this
"Letter Agreement"), Terrence Donati ("Donati") will surrender to the Company on
behalf of Maker 5,500,000 shares of the Company's common stock issued in
Donati's name (the "Settlement Shares") in full satisfaction of the Fleetmax
Note. In addition to the Settlement Shares, Donati will deliver to the Company
corresponding stock powers, duly executed, with signatures medallion guaranteed,
together with any additional instruments of assignment or conveyance necessary
to transfer the Settlement Shares to the Company.

         3.       Upon delivery to the Company of the Settlement Shares, the
Company will cancel the Fleetmax Note in full, as well as any guarantees of any
obligations related to the Fleetmax Note.

         4.       Concurrently with the delivery of the Settlement Shares and
the cancellation of the Fleetmax Note, the Company will issue to Donati a
warrant to purchase 5,500,000 shares of common stock of the Company (the
"Warrant"). The

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Warrant will be exercisable for a period of ten (10) years and shall contain an
exercise price of $0.21 per share. In addition, the warrant will contain
provisions which will grant to Donati the right to vote the 5,500,000 shares
purchasable under the Warrant on all matters submitted to the Company's
shareholders for a vote, regardless of whether the Warrant is exercised.

         5.       Upon delivery of the Settlement Shares to the Company and upon
cancellation of the Fleetmax Note and the delivery of the Warrant to Donati, the
parties will execute and deliver to each of the others a full release of any and
all claims relating to, arising from, or in any manner connected with the
Fleetmax Note.

         6.       The parties acknowledge and agree that the Warrant is being
issued as an inducement to Donati to surrender the Settlement Shares and is not
issued as compensation for Donati's services as on officer, director or employee
of the Company and shall not be deemed compensatory in any manner whatsoever.

         Please indicate your agreement with the above terms by signing where
indicated below.

                                                Sincerely,

                                                SHC Corp.

                                                /s/ Frank A. Contaldo
                                                ------------------------------
                                                Frank A. Contaldo
                                                Chief Executive Officer

Accepted and agreed to:

/s/ Terrence L. Donati
-------------------------------
Terrence L. Donati

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                                    EXHIBIT A

                           CALCULATION OF AMOUNTS DUE
                               UNDER FLEETMAX NOTE

                               AS OF JUNE 17, 1999



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---------------------------------------------------------------------------------

<S>                                                                 <C>
PRINCIPAL                                                           $1,146,133.00
---------------------------------------------------------------------------------
INTEREST:                                                              $91,690.64
                                                                       ----------
---------------------------------------------------------------------------------
                                    TOTAL:                          $1,237,823.60
---------------------------------------------------------------------------------

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