LETTER OF INTENT BETWEEN
                           NATIONAL D.E. SYSTEMS, INC.
                                       AND
                ENVIRONMENTAL PRODUCTS & TECHNOLOGIES CORPORATION


This Letter of Intent ("LOI") is entered into this 12th day of December, 1998 by
and  between  Environmental  Products &  Technologies  Corporation  ("EPTC"),  a
Delaware corporation (the "SELLER") and National D.E. Systems,  Inc. ("NDES"), a
Nevada corporation (the "BUYER"), with respect to the following facts:

RECITALS

NDES is a  corporation  duly formed and in good standing in the State of Nevada.
EPTC is a corporation duly formed and in good standing in the State of Delaware.

NOW,  THEREFORE,  in consideration of the mutual agreements,  the parties hereto
agree as follows:

         NDES is desirous of acquiring the mining claims and rights known as the
Tiger Claims from EPTC.

         On the  terms  of and  subject  to the  conditions  set  forth  in this
         Agreement, EPTC agrees to sell, convey, assign, transfer and deliver to
         NDES,  and NDES  agrees to  purchase  from EPTC,  at the  closing  (the
         "Closing") on or before  January 15, 1999  ("Closing  Date") the mining
         claims known as the "Tiger Claims"  further  described as being located
         in Malheur County, Oregon in Section 15, Township 18 South, Range 41 E.
         of Boise Meridian.

1.       Purchase Price.
         ---------------
         As consideration  for the sale,  conveyance,  assignment,  transfer and
         delivery of the Tiger  Claims to NDES,  NDES agrees to issue EPTC up to
         Eight  hundred  (800)  shares  of the  common  stock of  National  D.E.
         Systems,  Inc. which at the time of issue shall  represent no less than
         80% of all the  issued  and  outstanding  common  shares  of NDES.  The
         purchase  price may be reduced if the  purchaser  finds that the claims
         are not properly documented or that the books and records regarding the
         claims are not as represented  by EPTC. In addition,  EPTC may have the
         right to receive more shares of NDES if the books and records regarding
         its assets and  subsidiaries  are as represented.  The parties will use
         the due  diligence  period  to end no later  than  January  6,  1999 to
         complete the due  diligence  and no later than January 13, 1999 to come
         to a final agreement on the number of shares to be issued.

Tiger Claims LOI
Page 1 of  5
EPTC/National D.E. Systems, Inc.

                                       
<PAGE>

                            LETTER OF INTENT BETWEEN
                           NATIONAL D.E. SYSTEMS, INC.
                                       AND
                ENVIRONMENTAL PRODUCTS & TECHNOLOGIES CORPORATION
                                                      

2.       Transaction Structure.  NDES understands that EPTC has the authority or
         will obtain the authority to sell assign and transfer the assets herein
         described.

         A.       At the closing of the transaction (the "Closing"), the parties
                  will exchange the following:
                  1).      NDES will issue up to 800 shares of the common  stock
                           of NDES, and
                  2).      EPTC will deliver to NDES all of EPTC's right,  title
                           and interests to the Mining Claims listed below:

                           Name of Claims   BLM Serial No. County Instrument No.
                           --------------   -------------- ---------------------
                           Tiger #1         ORMC 153100    97-7312
                           Tiger #2         ORMC 153101    97-7313
                           Tiger #3         ORMC 153102    97-7314
                           Tiger #4         ORMC 153103    97-7315


3. EPTC agrees to the following:
   -----------------------------

A.            While the final  negotiations  and due diligence  process is being
              completed it will in no way materially change the status of any of
              the assets contemplated to be transferred hereby.

         B.       EPTC will  obtain all  necessary  corporate,  shareholder  and
                  other third-party approvals in form acceptable to NDES;

4. NDES Representation and Warranties the following:
   -------------------------------------------------

         A.       NDES is a newly formed  corporation  duly  organized,  validly
                  existing and in good  standing  under the laws of the State of
                  Nevada,  and has full  corporate  power and authority to enter
                  into  this   Agreement  and  to  carry  out  its   obligations
                  hereunder.

B.            The execution and delivery of this LOI and the final  consummation
              of the  transactions  contemplated  hereby  will not  violate  the
              Articles of Incorporation or the By-Laws of NDES or any agreement,
              contract or other instrument to which NDES is a party.


Tiger Claims LOI
Page 2 of  5
EPTC/National D.E. Systems, Inc.

<PAGE>

                            LETTER OF INTENT BETWEEN
                           NATIONAL D.E. SYSTEMS, INC.
                                       AND
                ENVIRONMENTAL PRODUCTS & TECHNOLOGIES CORPORATION
               

5. Further Assurances
   ------------------
         Prior to the closing there will be no change in the business activities
         of NDES and EPTC will in no way alter the status of the mining  claims.
         Each party to this  Letter of Intent  will have  approval  of any press
         release.

6. Notice
   ------
         Notice  will be deemed  to be given by one party to the other  party of
         this  Agreement  upon  personal  delivery by  messenger,  air  courier,
         express mail or certified registered mail, return receipt requested, or
         upon  facsimile or telegram,  or ten days after  mailing by first class
         mail by the party  giving  the  notice,  addressed  to the  parties  as
         indicated  below their  signatures to this  Agreement,  or to any other
         address or  facsimile  numbers  provided  to the  parties in writing in
         accordance with this Agreement by the party making the change.

7. Waivers
         If any party  shall at any time  waive any rights  hereunder  resulting
         from any  breach by the other  party of any of the  provisions  of this
         Agreement, such waiver is not to be construed as a continuing waiver of
         other  breaches  of the same or  other  provisions  of this  Agreement.
         Resort to any  remedies  referred to herein shall not be construed as a
         waiver of any other rights and remedies to which such party is entitled
         under this Agreement or otherwise.

8. Entire and Sole Agreement
   -------------------------
         This Agreement constitutes the entire agreement between the parties and
         supersedes all  agreements,  representations,  warranties,  statements,
         promises and undertakings, whether oral or written, with respect to the
         subject matter of this  Agreement.  This Agreement may be modified only
         by a written agreement signed by all parties.

9. Governing Law
   -------------
         This  Agreement  shall be governed by and construed in accordance  with
         the laws of the  State of  California.  The  venue  for any  action  or
         proceeding  brought  under this  Agreement  will be in the  appropriate
         forum in the County of Los Angeles, State of California.

10. Severability
    ------------
         The provisions of this Agreement are meant to be enforced  severally so
         that the determination that one or more  provisions  are enforceable or


Tiger Claims LOI                
Page 3 of  5                    
EPTC/National D.E. Systems, Inc.
                                
<PAGE>

                                                                     
                            LETTER OF INTENT BETWEEN                 
                           NATIONAL D.E. SYSTEMS, INC.               
                                       AND                           
                ENVIRONMENTAL PRODUCTS & TECHNOLOGIES CORPORATION    



         invalid shall not affect or render invalid any other  provision of this
         Agreement,  and such  other  provisions  shall  continue  to be in full
         forced in accordance with their terms.

11. Rights Cumulative
    -----------------
         All rights and remedies under this Agreement are  cumulative,  and none
         is  intended  to be  exclusive  of  another.  No delay or  omission  in
         insisting upon the strict observance of performance of any provision of
         this  Agreement,  or in  exercising  any  right  or  remedy,  shall  be
         construed as a waiver or relinquishment of such provision, nor shall it
         impair such right or remedy.  Every  right and remedy may be  exercised
         from time to time and as often as deemed expedient.

12. Captions
    --------
         The paragraph and other  headings  contained in this  Agreement are for
         reference  purposes only,  and shall not limit or otherwise  affect the
         meaning hereof.

13. Legal Holidays
    --------------
         In the case  where the date on which any action  required  to be taken,
         document required to be delivered or payment required to be made is not
         a business day in Los  Angeles,  California,  such action,  delivery or
         payment  need  not be made on that  date,  but may be made on the  next
         succeeding business day.

14. Counterparts
    ------------
         This  Agreement  may  be  executed  simultaneously  in  any  number  of
         counterparts,  each of  which  counterparts  shall be  deemed  to be an
         original,  and such counterparts  shall constitute but one and the same
         instrument.

15. Parties
    -------
         This  Agreement  shall  inure  solely  to the  benefit  of and shall be
         binding upon the parties hereto and their respective successors,  legal
         representatives  and  assigns,  and no other  person  shall  have or be
         construed  to have any  equitable  right,  remedy or claim  under or in
         respect of or by virtue of this  Agreement or any  provision  contained
         herein.

16. Authority
    ---------
         All  signatories to this Agreement do hereby declare that they have the
         authority  to execute  this  Agreement on behalf of the parties to this
         Agreement.


Tiger Claims LOI                
Page 4 of  5                    
EPTC/National D.E. Systems, Inc.
                               
<PAGE>

                            LETTER OF INTENT BETWEEN                  
                           NATIONAL D.E. SYSTEMS, INC.                
                                       AND                            
                ENVIRONMENTAL PRODUCTS & TECHNOLOGIES CORPORATION     
                                                                      


NDES: National D.E.  Systems, Inc.          EPTC: Environmental Products &
                                               Technologies Corporation


By:/s/Michael Empey                               By:/s/Morris Lerner
   ----------------                                  ----------------
     Michael Empey                                   Morris Lerner
     President                                       Secretary
     2020 Avenue Of The Stars                        5380 Sterling Center Dr.
     Suite 240                                       Westlake Village, CA 91361
     Los Angeles, CA 90067




Tiger Claims LOI                 
Page 5of  5                     
EPTC/National D.E. Systems, Inc.