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                                                                   EXHIBIT 10.41

                      [UNION BANK OF CALIFORNIA LETTERHEAD]



                                AMENDMENT LETTER



                                                   Commercial Banking Group
                                                   Union Bank of California
                                                   500 S. Main Street, Suite 200
                                                   Orange, CA 92868



November 17, 1998


Mr. William Healey, President
Smartflex Systems, Inc.
14312 Franklin Avenue
Tustin, CA 92680-7028

Re:     SECOND AMENDMENT ("Amendment") to the Amended and Restated Loan
        Agreement dated September 26, 1997 (this Amendment, the First Amendment
        dated October 1, 1998, and the Amended and Restated Loan Agreement
        together called the "Agreement")

Dear Mr. Healey:

In reference to the Agreement defined above between UNION BANK OF CALIFORNIA,
N.A. ("BANK") and SMARTFLEX SYSTEMS, INC. ("BORROWER"), Bank and Borrower desire
to amend the Agreement. Capitalized terms used herein which are not otherwise
defined shall have the meanings given them in the Agreement.

        1.     Amendment to the Agreement:

               (a)    Section 5.3, of the Agreement, is hereby amended in its
                      entirety to read as follows:

                      "SALE OF ASSETS, LIQUIDATION OR MERGER. Borrower will
                      neither liquidate nor dissolve nor enter into any
                      consolidation, merger, partnership or other combination,
                      nor convey, nor sell, nor lease all or the greater part of
                      its assets or business, nor purchase or lease all or the
                      greater part of the assets or business of another entity;
                      provided, however, that Borrower may merge or consolidate
                      with another entity, or may acquire, by purchase of stock
                      or by purchase of assets, all or the greater part of the
                      assets or business of another entity, if (a) Borrower is
                      the surviving entity, (b) the principal business of such
                      other entity is the same as that of Borrower, (c) such
                      merger, consolidation or acquisition is not contested, (d)
                      no part of the merger, consolidation or acquisition costs
                      represent Bank borrowings, and (e) the 



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Smartflex Systems, Inc.
2nd Amendment to Amended and Restated Loan Agreement
November 17, 1998
Page 2


                      consideration paid or to be paid by Borrower in connection
                      with such merger, consolidation or acquisition, whether in
                      the form of shares of Borrower's stock, cash or otherwise,
                      entered into or made by Borrower at any time on or after
                      the date of this Agreement, does not exceed, TEN MILLION
                      DOLLARS ($10,000,000) per transaction."

Except as specifically amended hereby, the Agreement shall remain in full force
and effect and is hereby ratified and confirmed.

This Second Amendment shall become effective when Bank shall have received the
acknowledgment copy of this Second Amendment executed by Borrower.

Very truly yours,

UNION BANK OF CALIFORNIA, N.A.


By:     //s// Robert Thomas
        -------------------------------
        Robert Thomas
Title:  Vice President


By:     //s// Anita Sardiya for
        -------------------------------
        Jim Heim
Title:  Vice President


AGREED AND ACCEPTED TO THIS 17 DAY OF NOVEMBER, 1998.

SMARTFLEX SYSTEMS, INC.


By:     //s// William Healey
        -------------------------------
        William Healey
Title:  President