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                                                                    Exhibit 10.3

                                 PROMISSORY NOTE
                                 ---------------

         $100,000.00                                       MAY 21, 2004

     For value received, Power Technology Inc., a Nevada Corporation, ("Maker")
promises to pay to the order of CORPORATE STRATEGIES, INC., a Delaware
corporation ("Payee"), in lawful money of the United States of America, the
principal sum of One Hundred Thousand and 00/100 Dollars ($l00,000.00). All
principal and any interest hereunder shall be payable at 1770 St. James Place,
Suite 116, Houston, TX 77056, or such other place that Payee may hereinafter
designate in writing.

     Principal under this note shall bear interest at the rate of eighteen
percent (18%) per annum from the date of funding until paid in full. All
principal and interest under this Note shall be paid in full on December 31,
2004. All interest that shall accrue in accordance herewith on the indebtedness
evidenced by this Note shall be computed on the basis of a year of 365 days.

     Each of the following events shall be herein referred to as an "Event of
Default": (i) the failure of Maker to maintain a public listing on the OTCBB,
NASDAQ, AMEX, OR NYSE exchanges or the failure to make timely filings of all
necessary requirements of all regulatory authorities, or (ii) the failure to
make payment of any of the principal or interest hereunder when due or on demand
by payee, (iii) if by July 15, 2004, the board of Directors of Maker has failed
to cause 67,000,000 shares of Maker's common stock to be set aside for transfer
to Payee as set forth in paragraph eight of this Note, (iv) the filing of a
petition in bankruptcy by Maker, or (v) the assignment of assets for the benefit
of creditors of Maker. It is especially agreed, that upon the occurrence of an
Event of Default, Payee or any other holder hereof at any time thereafter may,
at its option, (a) declare the entire unpaid principal of and accrued interest
on this Note immediately due and payable and upon notice to Maker and failure to
cure, the same shall become and shall be immediately due and payable; and (b)
take any and all other actions available to Payee or any holder under this Note
or any document given to secure this Note, at law, in equity or otherwise. The
failure of the holder hereof to exercise any of the foregoing options shall not
constitute a waiver of the right to exercise the salad upon the occurrence of a
subsequent default.

     In addition to all principal and accrued interest on this Note, Maker
agrees to pay (i) all reasonable costs and, expenses incurred by all owners and
holders of this Note in collecting this Note through reorganization, bankruptcy,
receivership or any other proceeding and (ii) reasonable attorney's fees when
and if this Note is placed in the hands of an attorney for collection after
default.

     It is the intention of the parties hereto to conform, strictly to
applicable usury laws as in effect from time to time during the term of this
Note. Accordingly, if any transaction or transactions contemplated hereby would
be usurious under applicable law (including the laws of the United States of
America, or of any other jurisdiction whose laws may be mandatorily applicable),
then, in that event, notwithstanding anything to the contrary in this Note, it
is agreed as follows: (i) the provisions of this paragraph shall govern and
control; (ii) the aggregate of an interest under applicable laws that is
contracted for, charged or received under this Note shall under no circumstances
exceed the maximum amount of interest allowed by applicable law, and any excess
shall be promptly refunded to Maker by Payee (or, if such consideration shall
have been paid in full, such excess shall be promptly refunded to Maker by
Payee); (iii,) neither Maker nor any other person or entity now or hereafter
liable in connection with this Note shall be obligated to pay the amount of such
interest to the extent that it is in excess of the maximum interest permitted by
the applicable usury laws; and. (iv) the effective rate of interest shall be
IPSO FACTO reduced to the maximum lawful interest rate.

                        Page l of 2 Page Promissory Note





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     Maker shall have the privilege to prepay this Note at any time, and from
time to time, in whole or part, without penalty or fee. Any prepayment of
principal under this Note shall include accrued interest to the date of
prepayment on the principal amount being prepaid.

     Maker and any other co-makers, endorsors, guarantors and sureties severally
(i) waive notice (including, but not limited to, notice of protest, notice of
dishonor and notice of intent to accelerate or notice of acceleration), demand,
presentment of payment, protest and filing of suit for the purpose of fixing
liability, (ii) consent that the time of payment hereof may be extended without
notice to them or any of them, (iii) expressly agree that it will not be
necessary for any holder hereof, in order to enforce payment of this Note by
them, to first institute suit or exhaust its remedies against Maker or any
others liable herefor, or to enforce its rights against any security herefor,
and (iv) consent to any extensions or postponements of time of payment of this
Note or any other indulgences with respect hereto without notice thereof to any
of them.

     In the event of default in the prompt payment of this note, holder may
present the note with an affidavit stating the loan is in default to the
Company's transfer agent. The presentation of this note and the affidavit of
default shall constitute irrevocable instructions to the transfer agent to
promptly issue 67,000,000 shares of fully paid and non-assessable shares of
common stock of Power Technology, Inc. to and in the name of Corporate
Strategies, Inc., which shall constitute full and complete payment for all sums
due under this Note. The Company fully and unconditionally guarantees that
67,000,000 shares of fully paid and non-assessable shares of common stock of
Power Technology, Inc, will be reserved and available for issuance to Corporate
Strategies, Inc upon default of in THE payment of any sum due pursuant to this
Note.

     This Note is further secured by the pledge of 27,157,483 shares of fully
paid and non-assessable shares of common stock of Power Technology, Inc.,
represented by certificate numbers 5324, 5339, 5674, 5768, and 5947 in the name
of Lee Balak, who specifically agrees to the pledge of this collateral and
acknowledges the possible loss of all shares in the event of their sale to pay
off this note. Payee will liquidate the shares in open market or private
transactions at such prices as are necessary in the sole opinion of Payee to
recover all loan principal, interest and costs of sales in the event that the
Company's transfer agent fails or refuses to issue and tender to Payee
67,000,000 shares of fully paid and non-assessable shares of common stock of.
Power, Technology, Inc. Any of the pledged 27,157,483 shares pledged by Lee
Balak remaining unsold after Payee has fully recovered all sums due under this
Note shall be returned to Pledgor.

     IN WITNESS WHEREOF, Maker has executed this Note as of the date set forth
above.

POWER TECHNOLOGY INC.

BY: /S/ LEE BALAK                                 /S/ LEE BALAK
    -------------------------------               ------------------------------
NAME:  LEE BALAK                                  LEE BALAK, INDIVIDUALLY AS
TITLE: CHIEF EXECUTIVE OFFICER AND                OWNER OF PLEDGED STOCK
       PRESIDENT