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                                                                     EXHIBIT 4.2

                             XENONICS HOLDINGS, INC.
                               WARRANT CERTIFICATE

         THIS WARRANT CERTIFICATE (the "Warrant Certificate") certifies that for
value received, ______________________________ (the "Holder"), is the owner of
this warrant (the "Warrant"), which entitles the Holder thereof to purchase at
any time on or before the Expiration Date (as defined below) _________ (_)
Shares (the "Warrant Shares") of fully paid non-assessable shares of the common
stock, par value $.001 per share, (the "Common Stock"), of XENONICS HOLDINGS,
INC. a Nevada corporation (the "Company"), at a purchase price of $______ per
Warrant Share (the "Purchase Price"), in lawful money of the United States of
America by bank or certified check, subject to adjustment as hereinafter
provided.

                  THE WARRANT REPRESENTED BY THIS CERTIFICATE HAS NOT BEEN
         REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"),
         AND IS SUBJECT TO RESTRICTIONS ON TRANSFERABILITY AS SET FORTH IN THIS
         CERTIFICATE. THIS WARRANT MAY NOT BE SOLD, TRANSFERRED, OR OTHERWISE
         DISPOSED OF IN THE ABSENCE OF AN EFFECTIVE REGISTRATION STATEMENT UNDER
         THE ACT OR AN OPINION OF COUNSEL, REASONABLY ACCEPTABLE TO COUNSEL FOR
         THE COMPANY, TO THE EFFECT THAT THE PROPOSED SALE, TRANSFER, OR
         DISPOSITION MAY BE EFFECTUATED WITHOUT REGISTRATION UNDER THE ACT.

         1.       WARRANT: PURCHASE PRICE.

         This Warrant shall entitle the Holder thereof to purchase the Warrant
Shares at the Purchase Price. The Purchase Price and the number of Warrant
Shares evidenced by this Warrant Certificate are subject to adjustment as
provided in Article 6.

         2.       EXERCISE: EXPIRATION DATE.

                  (a)      This Warrant is exercisable, at the option of the
         Holder, at any time after the date of issuance and on or before the
         Expiration Date (as defined below) by delivering to the Company written
         notice of exercise (the "Exercise Notice"), stating the number of
         Warrant Shares to be purchased thereby, accompanied by bank or
         certified check payable to the order of the Company for the Warrant
         Shares to be purchased. Within twenty (20) business days of the
         Company's receipt of the Exercise Notice accompanied by the
         consideration for the Warrant Shares being purchased, the Company shall
         issue and deliver to the Holder a certificate representing the Warrant
         Shares being purchased. In the case of exercise for less than all of
         the Warrant Shares represented by this Warrant Certificate, the Company
         shall cancel this Warrant Certificate upon the surrender thereof and
         shall execute and deliver a new Warrant Certificate for the balance of
         such Warrant Shares.

                  (b)      Expiration. The term "Expiration Date" shall mean
         5:00 p.m., New York time, on _____________________________, or if such
         date shall in the State of New York shall be a holiday or a day on
         which banks are authorized to close, then 5:00 p.m., New York time, the
         next following day which in the State of New York is not a holiday or a
         day on which banks are authorized to close.

         3.       RESTRICTIONS ON TRANSFER.

                  (b)      Restrictions. This warrant, and the Warrant Shares or
         any other security

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         issuable upon exercise of this Warrant may not be assigned,
         transferred, sold, or otherwise deposed of unless (i) there is in
         effect a registration statement under the Act covering such sale,
         transfer, or other disposition or (ii) the Holder furnishes to the
         Company an opinion of counsel, reasonably acceptable to counsel for the
         Company, to the effect that the proposed sale, transfer, or other
         disposition may be effected without registration under the Act, as well
         as such other documentation incident to such sale, transfer, or other
         disposition as the Company's counsel shall reasonably request.

                  (b)      Legend. Any Warrant Shares issued upon the exercise
         of this Warrant shall bear the following legend:

                  "The shares evidenced by this certificate were issued upon
                  exercise of a Warrant and may not be sold, transferred, or
                  otherwise disposed of in the absence of an effective
                  registration under the Securities Act of 1933 (the "Act") or
                  an opinion of counsel, reasonably acceptable to counsel for
                  the Company, to the effect that the proposed sale, transfer,
                  or disposition may be effectuated without registration under
                  the Act."

         4.       RESERVATION OF SHARES.

         The Company covenants that it will at all times reserve and keep
available out of its authorized Common Stock, solely for the purpose of issuance
upon exercise of this Warrant, such number of shares of Common Stock as shall
then be issuable upon the exercise of this Warrant. The company covenants that
all shares of Common Stock which shall be issuable upon exercise of this Warrant
shall be duly and validly issued and fully paid and non-assessable and free from
all taxes, liens, and charges with respect to the issue thereof.

         5.       LOSS OR MUTILATION.

         Upon receipt by the Company of reasonable evidence of the loss, theft,
destruction, or mutilation of this Warrant Certificate and, in the case of loss,
theft, or destruction, of indemnity reasonably satisfactory to the Company, or
in the case of mutilation, upon surrender and cancellation of the mutilated
Warrant Certificate, the Company shall execute and deliver in lieu thereof, a
new Warrant Certificate representing an equal number of Warrant Shares
exercisable thereunder.

         6.       ANTI-DILUTION PROVISIONS.

                  (a)      The number of shares of Common Stock and the Purchase
         Price per Warrant Share pursuant to this Warrant shall be subject to
         adjustment from time to time as provided for in this Section 6(a).
         Notwithstanding any provision contained herein, the aggregate Purchase
         Price for the total number of Warrant Shares issuable pursuant to this
         Warrant shall remain unchanged. In case the Company shall at any time
         change as a whole, by subdivision or combination in any manner or by
         the making of a stock dividend, the number of outstanding shares of
         Common Stock into a different number of shares, (i) the number of
         shares which the Holder of this Warrant shall have been entitled to
         purchase pursuant to this Warrant shall be increased or decreased in
         direct proportion to such increase or decrease of shares, as the case
         may be, and (ii) the Purchase Price per Warrant Share (but not he
         aggregate Purchase Price) in effect immediately prior to such change
         shall be increased or decreased in inverse proportion to such increase
         or decrease of shares, as the case may be.

                  (b)      In case of any capital reorganization or any
         reclassification of the capital stock of the Company or in case of the
         consolidation or merger of the Company with another corporation (or in
         the case of any sale, transfer, or other disposition to another
         corporation of all

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         or substantially all the property, assets, business, and goodwill of
         the Company), the Holder of this Warrant shall thereinafter be entitled
         to purchase the kind and amount of shares of capital stock which this
         Warrant entitled the Holder to purchase immediately prior to such
         capital reorganization, reclassification of capital stock,
         consolidation, merger, sale, transfer, or other disposition; and in any
         such case appropriate adjustments, shall be made in the application of
         the provisions of this Section 6 with respect to rights and interests
         thereafter of the Holder of this Warrant to the end that the provisions
         of this Section 6 shall thereafter be applicable, as near as reasonably
         may be, in relation to any shares or other property thereafter
         purchasable upon the exercise of this Warrant.

                  (c)      Fractional Shares. No certificate for fractional
         shares shall be issued upon the exercise of this Warrant, but in lieu
         thereof the Company shall purchase any such fractional shares
         calculated to the nearest cent.

                  (d)      Rights to the Holder. The Holder of this Warrant
         shall not be entitled to any rights of a shareholder of the Company in
         respect to any Warrant Shares purchasable upon the exercise hereof
         until such Warrant Shares have been paid for in full and issued to it.
         As soon as practicable after such exercise, the Company shall deliver a
         certificate or certificates for the number of full shares of Common
         Stock issuable upon such exercise, to the person or persons entitled to
         receive the same.

         7.       REPRESENTATIONS AND WARRANTIES.

         The Holder, by acceptance of this Warrant, represents and warrants to,
and covenants and agrees with, the Company as follows:

                           (i)      The Warrant is being acquired for the
                  Holder's own account for investment an not with a view toward
                  resale or distribution of any part thereof, and the Holder has
                  no present intention of selling, granting any participation
                  in, or otherwise distributing the same.

                           (ii)     The Holder is aware that the Warrant is not
                  registered under the Act or any state securities or blue sky
                  laws and, as a result, substantial restrictions exist with
                  respect to the transferability of the Warrant and the Warrant
                  Shares to be acquired upon exercise of this Warrant.

                           (iii)    The Holder is an accredited investor as
                  defined in Rule 501(a) of Regulation D under the Act and is a
                  sophisticated investor familiar with the type of risks
                  inherent in the acquisition of securities such as the Warrant,
                  and its financial position is such that it can afford to
                  retain the Warrant and the Warrant Shares for an indefinite
                  period of time without realizing any direct or indirect cash
                  return on this investment.

         8.       REGISTRATION.

                  (a)      Piggyback Registration. The Company agrees that if
         other than a registration statement filed to register the distribution
         of warrants and/or to register shares for selling shareholders to be
         prepared and filed within one year of the date hereof, at any time on
         or before the Expiration Date the Company registers any of its
         securities under the Act, whether for its own account or on behalf of
         selling stockholders the Company will provide the Holder with at least
         forty-five (45) days prior written notice of such intention and, upon
         request from the Holder, will cause the underlying shares issuable
         under this Warrant designated by the Holder to be registered under the
         Act (such event, a "Piggyback Registration").

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                  (b)      Piggyback Registration Procedures. A registration
         statement referred to in Section 8(a) shall be prepared and processed
         in accordance with the following terms and conditions:

                           (i)      The Holder agrees to cooperate in furnishing
                  promptly to the Company in writing any information requested
                  by the Company in connection with the preparation, filing, and
                  processing of such registration statement.

                           (ii)     The Company shall include in the
                  registration statement the shares of Common Stock proposed to
                  be included in the Piggyback Registration, subject to the
                  limitations set forth in Section 8(c).

                           (iii)    The Company shall prepare and file with the
                  Securities and Exchange Commission (the "SEC") such amendments
                  and supplements to such registration statement and the
                  prospectuses used in connections therewith as may be required
                  to comply with the provisions of the Act.

                           (iv)     The Company shall furnish to the Holder such
                  number of copies of each prospectus, including preliminary
                  prospectuses, in conformity with the requirements of the Act,
                  and such other documents, as the Holder may reasonably request
                  in order to facilitate the public sale or other disposition of
                  the shares owned by it.

                           (v)      The Company shall provide a transfer agent
                  and registrar for all such Common Stock registered pursuant to
                  this Section 8 not later than the Effective Date of such
                  registration statement.

                           (vi)     The Company shall, in connection with an
                  underwritten offering, enter into an underwriting agreement on
                  terms customarily contained in underwriting agreements with
                  respect to secondary distributions or combined primary and
                  secondary distributions, as appropriate.

                           (vii)    The Company shall make available for
                  inspection upon reasonable terms by the Holder, any
                  underwriter participating in any disposition pursuant to such
                  registration statement, and any attorney, accountant, or other
                  agent retained by an such Holder or underwriter, all financial
                  and other records, pertinent corporate documents and
                  properties of the Company, and cause the Company's officers,
                  directors and employees to supply all information reasonably
                  requested by any such Holder, underwriter, attorney,
                  accountant or agent in connection with the preparation of such
                  registration statement, provided that as a condition precedent
                  to such inspection, the Company may require such inspecting
                  party to execute and deliver a confidentiality agreement in a
                  form to be provided by the Company.

                           (viii)   The Holder shall not (until further notice)
                  effect sales of the shares covered by the registration
                  statement after receipt of telegraphic or written notice from
                  the Company to suspend sales to permit the Company to correct
                  or update registration statement or prospectus.

                  (c)      Limitations. Notwithstanding the foregoing, if a
         Piggyback Registration is an underwritten offering and the managing
         underwriter advises the Company in writing that in its opinion the
         total amount of securities requested to be included in such
         registration exceeds the amount of securities which can be sold in such
         offering, the Company will include in such registration: (i) first, all
         securities the Company proposes to sell, and (ii) second, up to such
         amount of securities requested to be included in such registration by
         the Holders of the Company, which in the opinion of such managing
         underwriter can be sold.

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         9.       FURNISH INFORMATION.

         The Company agrees that is shall promptly deliver to the Holder copies
of all financial statements, reports and proxy statements which the Company is
required to send to its shareholders generally.

         10.      INDEMNIFICATION.

                  (a)      The Company may require, as a condition to including
         any Common Stock in any Piggyback Registration pursuant to Section 8
         hereof that the Company shall have received an undertaking satisfactory
         to it from the Holder to indemnify and hold harmless the Company, each
         director of the Company, each officer of the Company who shall sign
         such registration statement, each person who participates as an
         underwriter (if such underwriter so requests) in the offering or sale
         of such securities and each person, if any, who controls such
         underwriter within the meaning of Section 15 of the Act or Section 20
         of the Exchange Act (each, an "Indemnified Person"), against any
         losses, claims damages, liabilities or expenses, joint or several, to
         which such person may become subject under the Act or otherwise,
         insofar as such losses, claims, damages, liabilities or expenses (or
         actions or proceedings in respect thereof) arise out of or are based
         upon (i) any untrue statement or alleged untrue statement of any
         material fact contained in any registration statement under which such
         securities were registered under the Act, any preliminary prospectus,
         final prospectus or summary prospectus contained therein, or any
         amendment thereof or supplement thereto, or any document incorporated
         by reference therein, or (ii) omission or alleged omission to state
         therein a material fact required to be stated therein or necessary to
         make the statements therein not misleading, if such actual or alleged
         statement or omission described in (i) or (ii) above was made in
         reliance upon and in conformity with written information furnished to
         the Company by such Holder for use in the preparation of such
         registration statement, preliminary prospectus, final prospectus,
         summary prospectus, amendment or supplement. Such indemnity shall
         remain in full force and effect regardless of any investigation made by
         or on behalf of the Company or any such director, officer,
         participating person or controlling person and shall survive the
         transfer of such securities by such Holder.

                  (b)      The Company shall agree, in connection with any
         registration statement filed pursuant to Section 8 hereof, that the
         Company shall indemnify each Holder selling Common Stock pursuant to
         such registration statement and each other person, if any, who controls
         such Holder within meaning of Section 15 of the Act or Section 20 of
         the Exchange Act, against any losses, claims, damages, liabilities or
         expenses, joint or several, to which such person may become subject
         under the Act or otherwise, insofar as such losses, claims, damages,
         liabilities or expenses (or actions or proceedings in respect thereof)
         arise out of or are based upon (i) any untrue statement or alleged
         untrue statement of any material fact contained in any registration
         statement under which such securities were registered under the Act,
         any preliminary prospectus, final prospectus or summary prospectus
         contained therein, or any amendment thereof or supplement thereto or
         any document incorporated by referenced therein, or (ii) any omission
         or alleged omission to state therein a material fact required to be
         stated therein or necessary to make the statements therein not
         misleading, provided that the Company shall not be liable in any such
         case to the extent that any such loss, claim, damage, liability or
         expense arises out of or is based upon an untrue statement or alleged
         untrue statement or omission or alleged omission made in reliance upon
         and in conformity with written information furnished to the Company by
         the Holder for use in preparation of such registration statement,
         preliminary prospectus, final prospectus, summary prospectus, amendment
         or supplement.

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                  (c)      If the Indemnification provided for in Sections 10(a)
         or 10(b) above is unavailable to an indemnified party in respect of any
         losses, claims, damages or liabilities referred to therein, then each
         indemnifying party in lieu of indemnifying such indemnified party
         thereunder shall contribute to the amount paid or payable by such
         indemnified party as a result of such losses, claims, damages or
         liabilities, in such proportion as is appropriate to reflect the
         relative fault of the indemnifying party on the one hand and of the
         indemnified parties on the other in connection with the statements or
         omissions which resulted in such losses, claims, damages or
         liabilities, as well as any other relevant equitable considerations.
         The relative fault of the indemnifying party and of the indemnified
         parties shall be determined by reference to, among other things,
         whether the untrue or alleged untrue statement of a material fact or
         the omission to state a material fact relates to information supplied
         by the indemnifying party, or by the indemnified parties, and the
         parties' relative intent, knowledge, access to information and
         opportunity to correct or prevent such statement or omission.

         The Company and the Holder agree that it would not be just and
equitable if contribution pursuant to this Section 10(c) were determined by pro
rata allocation or by any other method of allocation which does not take into
account the equitable considerations referred to in the immediately preceding
paragraph. The amount paid or payable by an indemnified party as a result of the
losses, claims, damages and liabilities or actions in respect thereof referred
to in the immediately preceding paragraph shall be deemed to include, subject to
the limitations set forth above, any legal or other expenses reasonably incurred
by such indemnified party in connection with investigating or defending any such
action or claim. No person guilty of fraudulent misrepresentation (within the
meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation.

         11.      MISCELLANEOUS.

                  (a)      Transfer Taxes: Expenses. The Holder shall pay any
         and all underwriters' discounts, brokerage fees, and transfer taxes
         incident to the sale or exercise of this Warrant or the sale of the
         underlying shares issuable thereunder, and shall pay the fees and
         expenses of any special attorneys or accountants retained by it.

                  (b)      Notice. Any notice or other communication required or
         permitted to be given to the Company shall be in writing and shall be
         delivered by certified mail with return receipt or delivered in person
         against receipt, as follows:

                             Xenonics Holdings, Inc.
                             2236 Rutherford Road, Suite 123
                             Carlsbad, CA 92008

                  (c)      Governing Law. This Warrant Certificate shall be
         governed by, and construed in accordance with, the laws of the State of
         Nevada, without reference to the conflicts of laws.

         IN WITNESS WHEREOF, the company has caused this Warrant Certificate to
be duly executed as of the date set forth below.

                                             XENONICS HOLDINGS, INC,

                                             By: _______________________________

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Date: ______________________________

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                           FORM OF EXERCISE OF WARRANT

         The undersigned hereby elects to exercise this Warrant as to
_______________________ Common Shares covered thereby. Enclosed herewith is a
bank or certified check in the amount of $____________.

Date: ____________________

                                           Name: _______________________________

                                           Address: ____________________________
                                           _____________________________________
                                           _____________________________________

                                           Signature: __________________________

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