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QUIETPOWER SYSTEMS, INC.
SUPPLEMENT TO PROSPECTUS DATED JUNE 12, 1997
QuietPower Systems, Inc. (the "Company") has entered into a Conversion and
Subscription Agreement, dated as of June 13, 1997, with Baltimore Gas and
Electric Company ("BG&E") (the "Conversion Agreement"). Pursuant to the
Conversion Agreement, BG&E has agreed to convert all of BG&E's rights to receive
royalties from the sale of the Company's transformer quieting systems and
purchase discounts on the Company's transformer quieting systems into 80,000
shares of the Common Stock of the Company. BG&E's rights arise out of a series
of agreements with the Company and Noise Cancellation Technologies, Inc.,
pursuant to which BG&E provided funding for the initial development of the
Company's transformer quieting system. See "Business-Utility Funded Development
Projects." As a result of the issuance of shares under the Conversion Agreement,
BG&E now holds 7.4% of the Company's issued and outstanding shares of Common
Stock and will hold 2.6% upon completion of this Offering. The Company will
recognize an expense of $540,000 in the quarter ended June 30, 1997 to give
effect to this transaction. In addition, the Company has granted piggyback
registration rights to BG&E relating to the 80,000 shares of Common Stock.
The date of this Supplement is June 17, 1997
