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                                                                   EXHIBIT 10.28


                               December 18, 1998


FWT, Inc.
701 Highlander
Suite 200
Arlington, TX 76015
Attention: Douglas Standley

     Re:   $25 Million Revolving Credit Facility dated as of November 12, 1997
           among FWT, Inc., Lenders and BT Commercial Corporation ("BTCC"),
           as Agent (the "Credit Agreement")

Gentlemen:

     You have previously advised us that Events of Default have occurred under 
the Credit Agreement under subsections 7.6A (Minimum Interest Coverage Ratio), 
7.6B (Maximum Leverage Ratio), and 7.6C (Minimum Consolidated EBITDA) for the 
period ending October 30, 1998 (the "Financial Covenant Events of Default"). 
Under subsection 4.2 of the Credit Agreement, the Company is not entitled to 
borrow upon the occurrence and continuance of an Event of Default, including 
the Financial Covenant Events of Default. Defined terms which are used herein 
but not otherwise defined herein shall have the meanings set forth therefor in 
the Credit Agreement.

     Over the last several weeks we have had numerous discussions with the 
Company and Baker Capital Corporation ("BCC") concerning the Company's current 
financial condition and future prospects. As we have previously discussed with 
you and BCC, we believe that the Company requires a capital infusion of 
$5,000,000. We have been advised that BCC has requested the Company to prepare 
a cash flow forecast prior to making a definitive decision regarding any 
additional equity contribution. We understand that the cash flow forecast is 
expected to be available by the close of business today.

     Notwithstanding the existence of the Financial Covenant Events of Default 
and without waiving any of BTCC's rights or remedies which arise by virtue of 
the occurrence and continuance of the Financial Covenant Events of Default or 
which may arise if any additional Events of Default occur under the Credit 
Agreement, we hereby advise you that BTCC is prepared, subject to the Company's 
compliance with the terms and conditions of the Credit Agreement (other than 
those relating to the Financial Covenant Events of Default), to make Loans to 
the Company from time to time in an amount which does not exceed 85% of 
Eligible Accounts Receivable which arise after the date of this letter.
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     The foregoing special lending arrangement will terminate in the event that 
additional Potential Events of Default or Events of Default arise under the 
Credit Agreement or in the event that BCC has not committed in writing to 
contribute an additional $5,000,000 in cash common equity by December 29, 1998, 
and has not actually contributed such additional $5,000,000 in cash common 
equity to the Company by January 13, 1999. This letter, and any delay or 
failure by BTCC to exercise at this time any of its rights and remedies, shall 
not impair any power, right or privilege granted to BTCC in the Credit 
Agreement or any other Loan Document or by law available to it or be construed 
to be waiver of or acquiescence in any Event of Default under the Credit 
Agreement or any other Loan Document.

     Except as modified hereby, the terms, provisions and conditions of the 
Credit Agreement and the other Loan Documents (as that term is defined under 
the Credit Agreement) shall remain in full force and effect and in all other 
respects are hereby ratified and confirmed.

                                        Very truly yours,

                                        BT COMMERCIAL CORPORATION,
                                        as Agent and Lender




                                            By: /s/ Thomas L. Ventling
                                                --------------------------------
                                                Thomas L. Ventling
                                                Senior Vice President