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                                                                         SBI USA
                                                         2361 C Drive, Suite 210
                                                                Irvine, CA 92612
                                                                  (949) 079 8330
                                                                  (940) 679 7280


August 1, 2003


HiEnergy Technologies, Inc.
1601 Alton Parkway
Unit B
Irvine, CA 92606

Attention: Bogdan Maglich
           Chief Executive Officer

Gentlemen:

         This will confirm the understanding and agreement (the "Agreement')
between SBI -- USA ("SBI") and HiEnergy Technologies, Inc. (together with its
successors, subsidiaries, or assigns, the "Company") as set forth below.

         1. Retention of SBI. The Company hereby engages SBI, and SB! accepts
such engagement, to provide to the Company a support letter (the "Support
Letter"), substantially in the form of the letter, addressed to William
Armstrong, Contracting Officer, Naval Surface Warfare Center, attached hereto as
Annex A.

         2. Offering and Sale. The Company acknowledges that, in the event that
SB! should be required to acquire any shares of common stock of the Company
("Shares"), as contemplated by the Support Letter, the proceeds of such
acquisition shall delivered against the delivery of securities of the Company in
accordance with, and subject to, the terms and conditions set forth herein. Any
such transaction shall be in compliance with Section 4(2) of the Securities Act
of 1933, as amended (the "Securities Act"), and, at the election of SBI,
Regulation D or Regulation S thereunder and state securities law, and be subject
to the registration provisions set forth herein.

         3. Fees and Expenses. In the event that the Company shall be awarded
the contract referenced in the Support Letter (Solicitation No- BAA N001 78-01
-Q-3040), the Company shall upon the execution of the contract pay to SBI a
non-refundable fee of $150,000. In the event that the Company shall not be
awarded the contract referenced in the Support Letter (Solicitation No. BAA N00l
78-01 -Q-3040), the Company shall upon the receipt of the first event of
communication from the Navy concerning notice of such potential award or
rejection pay to SBI a non-refundable fee of $50,000. In the event that the
Company shall receive either of the notices referenced in the two immediately
preceding sentences, but shall fail to promptly notify SBI or shall fail to
promptly pay such fee to SBI, such fee shall accrue interest at the rate of 24%
per annum. In addition to the fees set forth in this Paragraph


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August 1, 2003

Page 2

3, the Company shall pay all of its costs and expenses incident to the purchase
of the Shares, including without limitation, all fees and expenses of filings
with the Securities and Exchange Commission and the National Association of
Securities Dealers, Inc., in each case if applicable; all blue sky fees and
expenses; all fees of the counsel to SBI, fees of counsel and accountants for
the Company; any private placement documents; and blue sky memoranda.

         4. Conditions of SBI's Obligations; Corporate Changes:

         (a) The Company shall not be in violation of any term of its
Certificate of Incorporation or Bylaws or any material mortgage, indenture,
contract, agreement, instrument, judgment, decree, order, or any statute, rule
or regulation applicable to it, the violation of which shall have had or would
be likely to have a material adverse effect on the business, operations,
affairs, financial condition or prospects of the Company, or any of its
properties or assets, or shall have resulted or would be likely to result in any
material impairment of the right or ability of the Company to carry on its
business as now conducted or as proposed to be conducted or any material
liability on the part of the Company.

         (b) The Company shall, at the time of any acquisition of securities
contemplated hereby by SBI and for the period of 90 days prior thereto and
following the date of such acquisition, shall be in compliance in all material
respects with its reporting and other requirements under the Securities Exchange
Act of 1934, as amended (the "Exchange Act").

         (c) The registration statement relating to the resale of the Shares
(the "Registration Statement") shall have been declared effective under the
Securities Act. The Registration Statement, including the prospectus
constituting a part thereof, shall be at all times in conformity with the
requirements of the Securities Act and the applicable rules and regulations
whether under the Securities Act, the Exchange Act, or otherwise (the "Rules and
Regulations") of the Securities and Exchange Commission (the "Commission") under
the Securities Act Additional amendments or supplements to the Registration
Statement shall be prepared by the Company and filed with the Commission as may
hereafter be required in the reasonable opinion of SBI. The Commission shall not
have issued any order preventing or suspending the use of any final prospectus
(the "Prospectus") included in the Registration Statement or instituted
proceedings for that purpose, and the Prospectus shall conform to the
requirements of the Securities Act and the Rules; and at the time the
Registration Statement becomes effective under the Securities Act, and at all
times thereafter, (i) the Registration Statement and the Prospectus, and any
amendments or supplements thereto, contained and will contain all material
information required to be included therein by the Securities Act and the Rules
and Regulations and will conform to the requirements of the Securities Act and
the Rules and Regulations, and (ii) neither the Registration Statement nor the
Prospectus, or any amendments Or supplements thereto, will include any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements therein not misleading; provided, however that none of the
representations and warranties contained in this subparagraph shall apply to
information contained in or omitted from the Registration Statement or
Prospectus, or any amendment or supplement thereto, in reliance upon, and in
conformity with, written


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August 1, 2003

Page 3

information relating to SBI specifically and expressly furnished to the Company
by SBI for use in the preparation thereof.

         5. Representations and Covenants. The Company represents, warrants, and
covenants that:

         (a) The Company is currently in compliance in all material respects
with all requirements under the Exchange Act All filings with the Commission
conform to the requirements of the Exchange Act and the Rules and Regulations.
Each filing by the Company with the Commission contained all material
information required to be included therein by the Exchange Act and the Rules
and Regulations and will conform to the requirements of the Exchange Act and the
Rules and Regulations, and (ii) no filing made or to be made by the Company with
the Commission under the Exchange Act, or any amendments or supplements thereto,
contained when filed or will include when filed any untrue statement of a
material fact or omit to state a material f necessary to make the statements
therein not misleading. SBI understands that the Company's Form 10-KSB for
fiscal year 2003 is being filed late.

         (b) The Company agrees to indemnify SBI in accordance with the
indemnification provisions (the "Indemnification Provisions') attached to this
Agreement as Exhibit A, which Indemnification Provisions arc incorporated herein
and made a part hereof

         6. Statement of Intent: SBI intends to proceed with the transactions
conemplated hereby as soon as practicable after availability of the required
final documentation and the terms of this Letter Agreement have been satisfied;
provided, however, that SBI reserves the right not to proceed with the
transactions contemplated hereby if any condition set forth herein is not
satisfied on a timely basis.

         7. Other Matters:

         (a) If the Company or SB1 decides not to proceed with the transactions
contemplated hereby for any reason whatsoever, all expenses incurred by SBI in
connection with the transactions contemplated hereby, and in connection
herewith, will be repaid promptly by the Company in accordance with all
provisions described herein.

         (b) SBI and the Company agree that any controversy arising out of or
relating to this letter of intent or proposed offering contemplated hereby,
shall be settled by arbitration in accordance with the rules then in effect on
the National Association of Securities Dealers, Inc.

                     [REMAINDER OF PAGE INTENTIONALLY BLANK]


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August 1, 2003

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         If the foregoing correctly sets forth the understanding we have
heretofore reached regarding the proposed transactions, including the
Transaction, please sign and return the enclosed copy of this letter by August
1, 2003. If this Letter of Intent is not signed by August 1, 2003, and an
extension has not been mutually agreed upon in writing by the Company and SBI,
this Letter of intent will be considered void. By accepting this letter, the
Company agrees to keep this letter and all terms confidential and not to "shop"
it with any other investment bankers.


                                              Very truly yours,

                                              SBI-USA

                                              By: /s/ Shelly Singhal_
                                                  ------------------
                                                  Shelly Singhal
                                                  Managing Director


ACCEPTED AND AGREED TO
this 1st day of August, 2003


HIENERGY TECHNOLOGY, INC.

By: /s/ Bogdan C. Maglich
     ---------------------
     Name:  Bogdan C. Maglich
     Title: President & CEO


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August 1, 2003

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                                    EXHIBIT A

         SBI USA ("SBI") intends to conduct the transactions with HiEnergy
Technologies, Inc. (the "Company") contemplated by the Agreement (the
`Agreement') to which this Exhibit A is attached. Accordingly, the Company
agrees to indemnify and hold harmless SBI and its affiliates, its directors,
officers, agents, and employees and affiliates, and each other person, if any,
controlling SBI or any of its affiliates (collectively the "Indemnified
Persons"), from and against any losses, claims, damages, liabilities or expenses
(or actions, including shareholder actions, in respect thereof) related to or
arising out of such transactions or SBI's role in connection therewith, and will
reimburse the Indemnified Persons for all reasonable expenses (including
out-of-pocket expenses and SBI's counsel fees and expenses) as they are incurred
by the Indemnified Persons in connection with investigating, preparing or
defending any such action or claim, whether or not in connection with pending or
threatened litigation in which SBI or any Indemnified Person is a party. The
Company will not, however, be responsible to SBI for any losses, claims,
damages, liabilities, or expenses which are finally judicially determined to
have resulted primarily from such SBI's willful misconduct or bad faith or as a
result of the material misstatement or omission of any information relating to
SBI expressly provided thereby for inclusion in the Registration Statement (as
defined in the Agreement). The Company also agrees that none of the Indemnified
Persons shall have any liability to the Company for or in connection with the
services or matters pertaining to the Agreement except for any such liability
for losses, claims, damages, liabilities or expenses incurred by the Company
that results primarily from any SBI's willful misconduct or bad faith or any
such material misstatement or omission referenced in the immediately preceding
paragraph. If the forgoing indemnity is unavailable or insufficient to hold the
indemnified Persons harmless, then the Company shall contribute to the amount
paid or payable by the Indemnified Persons, in respect of the Indemnified
Persons, for losses, claims, damages, liabilities, or expenses in such
proportion as appropriately reflects the relative benefits received by, and
fault of, the Company, on the one hand and the Indemnified Persons, on the
other, in connection with the matters as to which such losses, claims, damages,
liabilities or expenses relate and other equitable consideration; provided,
however, the Company agrees that the aggregate contribution of all Indemnified
Persons shall in all cases be not more than the amount of paid by SBI to the
Company in connection with the transactions contemplated hereby. It is hereby
further agreed that the relative benefits to the Company on the one hand and the
Indemnified Persons on the other with respect to any transaction contemplated by
the Agreement shall be deemed to be in the same proportion as (I) the total
value of the transaction bears to (ii) the fees actually paid to SBI in respect
to such transaction. The foregoing Agreement shall be in addition to any rights
that SBI or any Indemnified Person may have at common law or otherwise. The
Company hereby consents to personal jurisdiction and service and venue in any
court in which any claim which is subject to this Agreement is brought against
SBI or any other Indemnified Person. If any action, proceeding, or investigation
is commenced as to which an Indemnified Person demands indemnification, the
Indemnified Person shall have the right to retain counsel of its own choice to
represent it, the Company shall pay the reasonable fees and expenses of such
counsel, and such counsel shall to the extent consistent with its professional
responsibilities cooperate with the Company


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August 1, 2003

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and any counsel designated by the Company; provided that the Company shall not
be responsible for the fees and expenses of more than one counsel. Nothing
herein is intended to relieve SBI of the risks incident to agreeing to make an
investment as contemplated by the support letter, without detracting from the
Company's liability for any breach or non-performance of the Agreement or this
Exhibit A.