AMENDMENT NO. 1 TO
                            STOCK PURCHASE AGREEMENT

         Amendment No. 1 to Stock Purchase Agreement dated as of August 9, 1999
between Quail Acquisition Corporation, a Massachusetts corporation ("Buyer"),
and Asahi/America, Inc., a Massachusetts corporation (the "Company;" such Stock
Purchase Agreement hereinafter being referred to as the "Agreement") made as of
October 21, 1999. Any capitalized terms used herein which are not otherwise
expressly defined in this Amendment are as defined in the Agreement.

         WHEREAS, Buyer and the Company desire to amend certain terms of the
Agreement as set forth herein;

         NOW, THEREFORE, in consideration of the premises and the payment of
other good and valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties agree as follows:

         1.       AMENDMENTS.  The Agreement is hereby amended as follows:

                  (a) The following section shall be added to Section 6:

         6.9      Prepayment Penalties Associated with the Arkansas Development
Finance Authority Industrial Development Bonds (Quail Piping Products, Inc.
Project), November 14, 1997 (the "Arkansas Bonds") and the County of Mohave,
Arizona Industrial Development Bonds (Quail Piping Products, Inc. Project),
Series 1998-A (the "Arizona Bonds"). Any prepayment penalties caused by the
prepayment of the Arkansas Bonds and/or the Arizona Bonds as a result of the
Disposition of Quail shall be shared equally by Quail and Asahi; provided,
however, that the portion of such prepayment penalties payable by Asahi shall
not exceed, in the aggregate, $160,000. Any prepayment penalties incurred in
excess of $320,000, in the aggregate, shall be the sole responsibility of Quail,
which amount shall be in addition to the fifty percent of the first $320,000
paid by Quail as per the previous sentence. Asahi shall pay Quail amounts owed
by it hereunder within 30 days of receiving documentation reasonably
satisfactory to it of the payments paid and owing by Quail with respect thereto.

         2.       RATIFICATION.  Except as specifically amended hereby
the terms of the Agreement are hereby ratified and confirmed in all respects.

         3.       AUTHORIZATION. This Amendment No. 1 to the Agreement has
been duly approved by the Special Committee constituted to act in connection
with this transaction and has been authorized by all necessary corporate action
on the part of the Company and no other corporate proceedings on the part of the
Company are necessary to authorize this


Amendment or to consummate the transactions so contemplated. This Amendment has
been duly executed and delivered by the Company and, assuming this Amendment
constitutes a valid and binding obligation of Buyer, constitutes a valid and
binding obligation of the Company enforceable against the Company in accordance
with its terms, except (i) as limited by applicable bankruptcy, insolvency,
reorganization, moratorium and other laws of general application affecting
enforcement of creditors' rights generally and (ii) as limited by laws relating
to the availability of specific performance, injunctive relief or other
equitable remedies.

         IN WITNESS WHEREOF, the undersigned have caused this Amendment to be
executed and delivered as of October 21, 1999.

                             QUAIL ACQUISITION CORPORATION

                             By: /s/ Leslie B. Lewis
                                 ----------------------------------
                                 Name:  Leslie B. Lewis
                                 Title:  Chairman

                             ASAHI/AMERICA, INC.

                             By: /s/ Leslie B. Lewis
                                 ----------------------------------
                                 Name:  Leslie B. Lewis
                                 Title:  President and Chief Executive Officer