Thursday, May 6, 1999

Trans Pacific Stores
555 Zang St., Suite 300
Lakewood, CO 80228

         Re:      Letter Amendment

Gentlemen:

         Reference is made to (i) the Secured Draw Down Promissory  Note,  dated
as of June 12, 1998 in the principal amount of $4 million ("Note") made by Covol
Technologies,  Inc.  ("Covol") to Trans Pacific Stores,  Ltd. ("Trans Pacific"),
(ii) the Loan  and  Security  Agreement,  dated as of June 12,  1998  ("Security
Agreement")  by and  between  Covol and Trans  Pacific,  (iii) the Common  Stock
Purchase  Warrants of Covol  Technologies,  Inc.,  certificate no.  WA-1998-287,
dated as of October 12, 1998, for 100,000 shares ("Trans Pacific Warrants") made
by Covol to Trans Pacific,  and (iv) the Common Stock Purchase Warrants of Covol
Technologies, Inc., certificate no. WA-001, dated as of August 19, 1997, for 85,
713 shares ("Diamond Jay Warrants"), made by Covol to Diamond Jay Ltd. Co.

         The parties to the above referenced  agreements and instruments  hereby
amend the terms there of as follows:

         Section 2 of the Note is  amended  to  provide  that $1  million of the
principal shall be due and payable on or before December 31, 1999 and $3 million
of the principal and any accrued but unpaid interest shall be due and payable on
April 30,  2000.  The entire $4 million  shall bear  interest  at 14 percent per
annum  beginning  June 13,  1999 and shall  then be  payable  monthly in arrears
beginning June 30, 1999.

         Section 3 of the  Security  Agreement  is amended  to provide  that the
August 1996 Larson  Promissory Note and the interest in future  quarterly earned
royalties  payable to Covol  pursuant to section  3.4 of the  License  Agreement
between Appalachian  Synfuel, LLC and Covol dated December 4, 1997 shall each be
held as  collateral  for the full amounts due under the Note until the Note,  as
amended herein, is repaid in full.

         The Trans  Pacific  Warrants  and the  Diamond  Jay  Warrants  are both
amended to provide that the Exercise Periods shall be extended for one year from
the original  Termination  Dates and that the Per Share Warrant Prices (exercise
prices)  shall be the lower of the average  closing  share price of Covol common
stock for the five days immediately before May 6, 1999 or June 12, 1999.

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         This letter agreement may be executed in one or more counterparts,  all
of which shall be considered one and the same letter agreement.

                                                     Very truly yours,

                                                     Covol Technologies, Inc.

                                                     /s/ Steven G. Stewart 
                                                     -------------------------
                                                     Steven G. Stewart
                                                     Chief Financial Officer

Accepted and Agreed to as of the date first set forth above:

Trans Pacific Stores, Ltd.



By:   /s/ Donald V. Berlanti              
      ------------------------
Name:   Donald V. Berlanti              
Title:     Chairman