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                                                                   EXHIBIT 10.21

THIS WARRANT AND THE SHARES OF COMMON STOCK ISSUABLE UPON EXERCISE HEREOF HAVE
NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE
SECURITIES LAWS AND MAY NOT BE SOLD, TRANSFERRED OR OTHERWISE DISPOSED OF IN THE
ABSENCE OF REGISTRATION UNDER SAID ACTS AND ALL OTHER APPLICABLE SECURITIES LAWS
UNLESS AN EXEMPTION FROM REGISTRATION IS AVAILABLE.

                               WARRANT TO PURCHASE

                             SHARES OF COMMON STOCK

                                       OF

                     MCLAREN PERFORMANCE TECHNOLOGIES, INC.


Number of Shares:     43,367
Date of Issuance:     December 7, 2001
Date of Expiration:   February 28, 2003


          FOR VALUE RECEIVED, the undersigned, McLaren Performance Technologies,
Inc., a Delaware corporation (the "Company"), hereby certifies that EMM McLaren
Investment Company, L.L.C., a Michigan limited liability company located at 1845
Maxwell, Suite 101, Troy, Michigan 48084 ("EMM"), is entitled to subscribe for
and purchase, during the period specified in this Warrant, 43,367 shares of
common stock of the Company, at an exercise price per share equal to the Per
Share Exercise Price then in effect, subject, however, to the provisions and
upon the terms and conditions hereinafter set forth.

1.   Definitions. Certain capitalized terms used in this Warrant shall have the
     following meanings:

          (a) "Act" means the Securities Act of 1933, as amended, or any similar
federal statute, and the rules and regulations of the Commission promulgated
thereunder, all as the same shall be in effect at the time.

          (b) "Additional Shares of Common Stock" means all shares of Common
Stock issued by the Company after the date hereof, except (i) the Warrant Stock,
and (ii) any shares of Common Stock issued pursuant to the exercise of stock
options issued by the Company to its employees pursuant to any Company stock
option plans.

          (c) "Common Stock" means the Company's common stock, $0.00001 par
value.

          (d) "Commission" means the United States Securities and Exchange
Commission or any successor

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agency.

          (e) "Convertible Securities" means evidences of indebtedness, shares
of stock or other securities that are convertible into or exchangeable for
shares of Common Stock.

          (f) "Expiration Date" means February 28, 2003.

          (g) "Holder" means EMM, or any permitted assignee who may have
acquired this Warrant in accordance with the terms of Section 7.

          (h) "Issuance Date" means December 7, 2001.

          (i) "Per Share Exercise Price" shall mean $1.00 per share.

          (j) "Per Share Market Price" means on any particular date (a) the
closing bid price per share of the Common Stock on such date on NASDAQ or other
registered national stock exchange on which the Common Stock is then listed or
if there is no such price on such date, then the closing bid price on such
exchange or quotation system on the date nearest preceding such date, or (b) if
the Common Stock is not listed then on NASDAQ or any registered national stock
exchange, the closing bid price for a share of Common Stock in the
over-the-counter market, as reported by the OTC Bulletin Board or in the
National Quotation Bureau Incorporated or similar organization or agency
succeeding to its functions of reporting prices) at the close of business on
such date, or (c) if the Common Stock is not then reported by the OTC Bulletin
Board or the National Quotation Bureau Incorporated (or similar organization or
agency succeeding to its functions of reporting prices), then the average of the
"Pink Sheet" quotes for the relevant conversion period, as determined in good
faith by McLaren's Board of Directors, or (d) if the Common Stock is not then
publicly traded, the fair market value of a share of Common Stock as determined
in good faith by the Company's Board of Directors.

          (k) "Person" means any individual, corporation, partnership, trust,
unincorporated organization and any government, and any political subdivision,
instrumentality or agency thereof.

          (l) "Term" shall have the meaning set forth in Section 2.

          (m) "Warrant Stock" means the 43,367 shares of Common Stock issuable
upon the exercise of this Warrant, subject to adjustment in accordance with
Section 8.

          (n) "Warrant Office" means 32233 West Eight Mile Road, Livonia,
Michigan 48152, or such other office of the Company or of any transfer agent of
the Common Stock in the continental United States as to which written notice has
previously been given to the then current Holder of this Warrant.

2.   Exercisability; Expiration. The right to subscribe for and purchase not
less than all of the shares of Warrant Stock represented hereby shall commence
on the Issuance Date and shall expire at 5:00 p.m., Detroit time, on the
Expiration Date (such period being the "Term"). The purchase rights represented
by this Warrant may be exercised in whole at

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any time and from time to time during the Term. Rights to purchase shares under
this Warrant shall expire and may not be exercised after at 5:00 p.m., eastern
daylight savings time, on Expiration Date.

3.   Method of Exercise. To the extent this Warrant is exercisable, to exercise
this Warrant, the Holder shall deliver to the Company at the Warrant Office in
accordance with Section 13: (a) a Notice of Exercise substantially in the form
attached hereto as Exhibit A duly executed by the Holder, (b) payment of an
amount equal to the product of the Per Share Exercise Price multiplied by the
number of shares of Warrant Stock, which shall be made in cash or by certified
or bank cashier's check payable to the order of the Company, and (c) this
Warrant. An exercise of this Warrant shall be deemed to be effective upon
receipt by the Company of all of the items described in the preceding sentence.
The Company shall thereafter, as promptly as practicable, cause to be issued and
delivered to the Holder a certificate or certificates representing the Warrant
Stock specified in the Notice of Exercise. The stock certificate or certificates
so delivered shall be in denominations of shares as may be specified in said
notice and shall be issued in the name of the Holder. The Company shall pay all
expenses, taxes (excluding capital gains and income taxes) and other charges
payable in connection with the preparation, issuance and delivery of stock
certificates.

4.   Shares to be Fully Paid and Non-Assessable. The Warrant Stock shall be
validly issued, fully paid, non- assessable and free from preemptive rights.

5.   No Fractional Shares to be Issued. The Company shall not be required upon
any exercise of this Warrant to issue a certificate representing any fraction of
a share of Common Stock.

6.   Legend on Warrant Stock. Each certificate representing the Warrant Stock,
unless at the time of exercise such shares are registered under the Act, shall
bear substantially the following legend (and any additional legend required by
any national securities exchanges upon which such shares may, at the time of
such exercise, be listed or under applicable securities laws): THE SECURITIES
REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE FEDERAL
SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE. THEY
MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, PLEDGED, HYPOTHECATED, ENCUMBERED, OR
OTHERWISE DISPOSED OF UNLESS, IN THE OPINION OF COUNSEL REASONABLY ACCEPTABLE TO
THE ISSUER, SUCH TRANSFER WOULD BE PURSUANT TO AN EFFECTIVE REGISTRATION
STATEMENT UNDER SAID ACTS OR PURSUANT TO AN EXEMPTION FROM SUCH REGISTRATION.

7.   Ownership of Warrant; Restrictions on Transfer. The Company may deem and
treat the Person in whose name this Warrant is registered as the Holder and
owner hereof (notwithstanding any notations of ownership or writing hereon made
by anyone other than the Company) for all purposes and shall not be affected by
any notice to the contrary. Neither this Warrant, nor any rights hereunder, are
transferable, in whole or in part, without the prior written consent of the
Company.

8.   Adjustments to Number of Shares of Warrant Stock. The number of shares of
Warrant Stock shall be subject to adjustment from time to time in accordance
with this Section 8, including the limitations set forth in Subsection 8(h).

         (a)  Stock Dividends, Subdivision and Combination. In the event that,
during the Term, the Company

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shall: (i) pay a dividend or other distribution of Common Stock to the holders
of its outstanding Common Stock, (ii) subdivide its outstanding shares of Common
Stock into a larger number of shares of Common Stock, or (iii) combine its
outstanding shares of Common Stock into a smaller number of shares of Common
Stock; then the number of shares of Warrant Stock shall be adjusted so as to
consist of the number of shares of Common Stock that a record holder of the
number of shares of Common Stock comprising the Warrant Stock immediately prior
to the happening of such event would own or be entitled to receive after the
happening of such event. The adjustments required by this subsection shall be
made whenever and as often as any specified event requiring an adjustment shall
occur.

        (b)  Certain Other Dividends and Distributions. In the event that,
during the Term, the Company intends to pay a dividend or other distribution of:
(i) cash, or (ii) any evidences of its indebtedness, any other securities or
property of any nature whatsoever (other than cash or Common Stock); then at
least ten (10) business days prior to the record date to determine shareholders
entitled to receive such dividend or distribution, the Company shall give notice
of such proposed dividend or distribution to the Holder for the purpose of
enabling the Holder to exercise this Warrant, and thereby participate in such
dividend or distribution.

        (c)  Issuance of Additional Shares. In the event that, during the Term,
the Company shall issue or sell any Additional Shares of Common Stock for a
consideration per share less than the Per Share Market Price, then the number of
shares of Warrant Stock shall be adjusted to that number determined by
multiplying the number of shares of Warrant Stock immediately prior to such
adjustment by a fraction: (i) the numerator of which shall be the sum of the
number of shares of Common Stock issued and outstanding, plus the number of
Additional Shares of Common Stock deemed to be outstanding pursuant to
Subsection 8(d) immediately prior to the issuance of such Additional Shares of
Common Stock, plus the number of such Additional Shares of Common Stock so
issued; and (ii) the denominator of which shall be the sum of the number of
shares of Common Stock issued and outstanding, plus the number of Additional
Shares of Common Stock deemed to be outstanding pursuant to Subsection 8(d)
immediately prior to the issuance of such Additional Shares of Common Stock,
plus the number of shares of Common Stock that the aggregate consideration for
the total number of such Additional Shares of Common Stock so issued would
purchase at the Per Share Market Price. The provisions of this Subsection 8(c)
shall not apply to any issuance of Additional Shares of Common Stock for which
an adjustment is provided under Subsection 8(a). No adjustment of the number of
shares of Warrant Stock shall be made under this subsection upon the issuance of
any Additional Shares of Common Stock that are issued pursuant to the exercise
of any warrants or other subscription or purchase rights or pursuant to the
exercise of any conversion or exchange rights in any Convertible Securities, if
any such adjustment shall previously have been made upon the issuance of such
warrants or other rights or upon the issuance of such Convertible Securities (or
upon the issuance of any warrant or other rights therefor) pursuant to
Subsection 8(d).

        (d)  Issuance of Warrants, Convertible Securities or Other Rights. In
the event that, during the Term, the Company shall issue or sell any warrants or
other rights to subscribe for or purchase any Additional Shares of Common Stock
or any Convertible Securities (whether or not the rights to exchange or convert
thereunder are immediately exercisable) and the consideration per share for
which Additional Shares of Common Stock may at any time thereafter be issuable
pursuant to such warrants or other rights or pursuant to the terms of such
Convertible Securities shall be lower than the Per Share Exercise Price, then
the number of shares of Warrant Stock shall be adjusted as provided in
Subsection 8(c) and the aggregate consideration for such maximum number of
Additional Shares of Common Stock shall be deemed to be the minimum
consideration received and receivable by the Company

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for the issuance of such Additional Shares of Common Stock pursuant to such
warrants or other rights or pursuant to the terms of such Convertible
Securities. No adjustment of the number of shares of Warrant Stock shall be made
under this Subsection 8(d) upon the issuance of any Convertible Securities that
are issued pursuant to the exercise of any warrants or other subscription or
purchase rights therefor, if any such adjustment shall previously have been made
upon the issuance of such warrants or other rights pursuant to this Subsection
8(d).

        (e)  Superseding Adjustment to Warrant Stock. If, at any time after any
adjustment of the number of shares of Warrant Stock shall have been made
pursuant to the foregoing Subsection 8(d) on the basis of the issuance of
warrants or other rights or the issuance of other Convertible Securities, or
after any new adjustments of the number of shares comprising the Warrant Stock
shall have been made pursuant to this Subsection 8(e), (i) such warrants or
rights or the right of conversion or exchange in such other Convertible
Securities shall expire, and a portion of such warrants or rights, or the right
of conversion or exchange in respect of a portion of such other Convertible
Securities, as the case may be, shall not have been exercised, and/or (ii) the
consideration per share, for which shares of Common Stock are issuable pursuant
to such warrants or rights or the terms of such other Convertible Securities,
shall be increased for any reason, then such previous adjustment shall be
rescinded and annulled and the Additional Shares of Common Stock that were
deemed to have been issued by virtue of the computation made in connection with
the adjustment so rescinded and annulled shall no longer be deemed to have been
issued by virtue of such computation. Thereupon, a recomputation shall be made
of the effect of such rights or options or other Convertible Securities on the
basis of (x) treating the number of Additional Shares of Common Stock, if any,
theretofore actually issued or issuable pursuant to the previous exercise of
such warrants or rights or such right of conversion or exchange, as having been
issued on the date or dates of such exercise and for the consideration actually
received and receivable therefor, and (y) treating any such warrants or rights
or any such other Convertible Securities that then remain outstanding as having
been granted or issued immediately after the time of such increase of the
consideration per share for which shares of Common Stock are issuable under such
warrants or rights or other Convertible Securities; and, if and to the extent
called for by the foregoing provisions of this Section 8 on the basis aforesaid,
a new adjustment of the number of shares of Warrant Stock shall be made, which
new adjustment shall supersede the previous adjustment so rescinded and
annulled.

        (f)  Other Provisions Applicable to Adjustment Under This Section. The
following provisions shall be applicable to the making of adjustments of the
number of shares of Warrant Stock hereinbefore provided for in this Section 8:

             (i)  Treasury Stock. The sale or other disposition of any issued
        shares of Common Stock owned or held by or for the account of the
        Company shall be deemed an issuance thereof for the purposes of this
        Section 8.

             (ii) Computation of Consideration. To the extent that any
        Additional Shares of Common Stock or any Convertible Securities or any
        warrants or other rights to subscribe for or purchase any Additional
        Shares of Common Stock or any Convertible Securities shall be issued for
        a cash consideration, the consideration received by the Company therefor
        shall be deemed to be the amount of the cash received by the Company
        therefor, or, if such Additional Shares of Common Stock or Convertible
        Securities are offered by the Company for subscription, the subscription
        price, or, if such Additional Shares of Common Stock or Convertible
        Securities are sold to underwriters or dealers for public offering
        without a subscription offering,

<PAGE>

     the initial public offering price, in any such case excluding any amounts
     paid or receivable for accrued interest or accrued dividends (but without
     deduction of any compensation, discounts or expenses paid or incurred by
     the Company for and in the underwriting of, or otherwise in connection
     with, the issuance thereof). To the extent that such issuance shall be for
     a consideration other than cash, then, except as herein otherwise expressly
     provided, the amount of such consideration shall be deemed to be the fair
     value of such consideration at the time of such issuance as determined in
     good faith by the Board of Directors of the Company (but without deduction
     of any compensation, discounts or expenses paid or incurred by the Company
     for and in the underwriting of, or otherwise in connection with, the
     issuance thereof). In case any Additional Shares of Common Stock or
     Convertible Securities or any warrants or other rights to subscribe for or
     purchase such Additional Shares of Common Stock or Convertible Securities
     shall be issued in connection with any merger in which the Company issues
     any securities, the amount of consideration therefor shall be deemed to be
     the fair value, as determined in good faith by the Board of Directors of
     the Company, of such portion of the assets and business of the nonsurviving
     corporation as such Board in good faith shall determine to be attributable
     to such Additional Shares of Common Stock, Convertible Securities, warrants
     or other rights, as the case may be. In the event of any consolidation or
     merger of the Company in which the Company is not the surviving corporation
     or in the event of any sale of all or substantially all of the assets of
     the Company for stock or other securities of any corporation, the Company
     shall be deemed to have issued a number of Additional Shares of Common
     Stock or Convertible Securities of the other corporation computed on the
     basis of the actual exchange ratio on which the transaction was predicated,
     and the consideration received for such issuance shall be equal to the fair
     market value, as determined in good faith by the Board of Directors of the
     Company, on the date of such transaction, of such stock or securities of
     the other corporation, and if any such calculation results in adjustment of
     the number of shares of Warrant Stock immediately prior to such merger,
     conversion or sale for purposes of this Subsection 8(f), such merger,
     conversion or sale shall be deemed to have been made after giving effect to
     such adjustment. The consideration for any Additional Shares of Common
     Stock issuable pursuant to any warrants or other rights to subscribe for or
     purchase the same shall be the consideration received by the Company for
     issuing such warrants or other rights, plus the additional consideration
     payable to the Company upon the exercise of such warrants or other rights.
     The consideration for any Additional Shares of Common Stock issuable
     pursuant to the terms of any Convertible Securities shall be the
     consideration received by the Company for issuing any warrants or other
     rights to subscribe for or purchase such Convertible Securities, plus the
     consideration paid or payable to the Company in respect of the subscription
     for or purchase of such Convertible Securities, plus the additional
     consideration, if any, payable to the Company upon the exercise of the
     right of conversion or exchange in such Convertible Securities.

          (iii)  Fractional Interests. In computing adjustments under this
     section, fractional interests in Common Stock shall not be taken into
     account.

          (iv)   When Adjustment Not Required; Abandonment of Plan for Dividend
     and the Like. If the Company shall declare a dividend or distribution of,
     or grant subscription or purchase rights with respect to, Common Stock as
     described in this Section 8 and shall, thereafter, legally abandon its plan
     to pay or deliver such dividend, distribution, subscription or purchase
     rights, then thereafter no adjustment shall be required and any such
     adjustment previously made in respect thereof shall be rescinded and
     annulled.

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          (g) Reorganization, Reclassification, Merger, Consolidation or
Disposition of Assets. In case the Company shall reorganize its capital,
reclassify its capital stock, merge or consolidate into another corporation,
then the number of shares of stock purchasable upon exercise of this Warrant
shall be adjusted to consist of the number of shares of stock or other
securities that a record holder of the number of shares of Common Stock
purchasable upon exercise of this Warrant immediately prior to such event would
own or be entitled to receive immediately after such event.

          (h) No Adjustment. Notwithstanding the foregoing, an adjustment as
provided in this Section 8 shall not be made if: (a) the Company offers
securities to the public pursuant to a registration statement under the Act, (b)
the Company issues securities pursuant to the acquisition by the Company of any
product, technology, know-how or another corporation by merger, purchase of all
or substantially all of the assets, or any other reorganization whereby the
Company owns over fifty percent (50%) of the voting power of such corporation,
(c) Company issues shares of its capital stock in connection with any stock
split, stock dividend or the Company issues any shares of common stock of the
Company pursuant to options, warrants or rights granted before August 1, 2001,
or granted before or after the date hereof if granted to purchase shares of such
common stock in favor of employees, directors, officers, strategic partners or
consultants of the Company or any subsidiary thereof pursuant to a stock option
plan or agreement approved by the Company's Board of Directors; provided that
such stock options thereunder, if granted after the date hereof, are granted at
a conversion or exercise price that the Company's Board of Directors determines
in good faith is not less than the fair market value of the securities into
which they are exercisable as of the date of grant, or (d) the Company converts
any securities into Common Stock pursuant to the Company's Certificate of
Incorporation, as amended.

          (i) Notice of Adjustment. Whenever the Company takes any action that
causes the composition of the Warrant Stock to change under Subsections 8(a)
through 8(g), the Company shall provide the Holder with written notice, in
accordance with Section 13, of such change and the number of shares of Warrant
Stock for which this Warrant is or will become exercisable. In addition to any
other notice required hereunder, the Company shall provide the Holder with a
copy of any notice that the Company is required to provide those Persons holding
shares of Common Stock on the same date such persons receive such notice.

9.   Certain Covenants of the Company. The Company has taken all action
necessary to authorize the issuance of this Warrant and the issuance of shares
of Common Stock upon exercise hereof. The Company covenants and agrees that it
will reserve and set apart and have at all times, free from preemptive rights, a
number of shares of authorized but unissued Common Stock or other securities
deliverable upon the exercise of this Warrant from time to time sufficient to
enable it at any time to fulfill all its obligations hereunder.

10.  Entire Agreement. This Warrant contains the entire agreement between the
Holder and the Company with respect to the Warrant Stock and supersedes all
prior arrangements or understandings with respect thereto.

11.  Waiver and Amendment. Any term or provision of this Warrant may be waived
at any time by the party that is entitled to the benefits thereof, and any term
or provision of this Warrant may be amended or supplemented at any time by
agreement of the Holder and the Company, except that any waiver of any term or
condition, or any amendment or supplementation, of this Warrant must be in
writing. A waiver of any breach or failure to enforce any of the terms or

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conditions of this Warrant shall not in any way affect, limit or waive a party's
rights hereunder at any time to enforce strict compliance thereafter with any
term or condition of this Warrant.

12.  Illegality.  In the event that any one or more of the provisions contained
in this Warrant shall be determined to be invalid, illegal or unenforceable in
any respect for any reason, the validity, legality and enforceability of any
such provision in any other respect and the remaining provisions of this Warrant
shall not, at the election of the party for whom the benefit of the provision
exists, be in any way impaired.

13.  Notices. Any notice or other document required or permitted to be given or
delivered to the Holder shall be delivered personally, or sent by certified or
registered mail, to the Holder at the last address shown on the books of the
Company maintained at the Warrant Office for the registration of the Warrant or
at any more recent address of which any Holder shall have notified the Company
in writing in accordance with this Section 13. Any notice or other document
required or permitted to be given or delivered to the Company shall be delivered
personally, or sent by certified or registered mail, to the Warrant Office,
attention: Chief Financial Officer. Any notice given by either party hereunder
shall be deemed to be effective upon receipt.

14.  Limitation of Liability; Not A Shareholder. No provision of this Warrant
shall be construed as conferring upon the Holder the right to vote, consent,
receive dividends or receive notice other than as herein expressly provided in
respect of meetings of shareholders for the election of directors of the Company
or any other matter whatsoever as a shareholder of the Company. No provision
hereof, in the absence of affirmative action by the Holder to purchase Warrant
Stock, and no enumeration herein of the rights or privileges of the Holder,
shall give rise to any liability of such Holder for the purchase price of any
Warrant Stock or as a shareholder of the Company, whether such liability is
asserted by the Company or by creditors of the Company.

15.  Loss, Destruction, Etc. of Warrant. Upon receipt of evidence satisfactory
to the Company of the loss, theft, mutilation or destruction of the Warrant, and
in the case of any such loss, theft or destruction, upon delivery of a bond of
indemnity in such form and amount as shall be reasonably satisfactory to the
Company, or in the event of such mutilation, upon surrender and cancellation of
the Warrant, the Company shall make and deliver a new warrant, of like tenor, in
lieu of such lost, stolen, destroyed or mutilated Warrant. Any Warrant issued
under the provisions of this Section 15 in lieu of any Warrant alleged to be
lost, destroyed or stolen, or in lieu of any mutilated Warrant, shall constitute
an original contractual obligation on the part of the Company.

        IN WITNESS WHEREOF, the Company has executed this Warrant as of the day
and year first above written.

                            MCLAREN PERFORMANCE TECHNOLOGIES, INC.

                            By: /s/ Steven Rossi
                                ------------------------------------------------
                                      Steven Rossi, President

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                                    EXHIBIT A

                               NOTICE OF EXERCISE

Dated: _______________

        The undersigned hereby irrevocably elects to exercise its right to
purchase 43,367 shares of the common stock, $0.00001 par value per share, of
McLaren Performance Technologies, Inc., such right being pursuant to a Warrant
dated December 7, 2001, as issued to EMM McLaren Investment Company, L.L.C. (the
"Warrant"), and remits herewith the sum of $43,367 in payment for same in
accordance with the terms of the Warrant.

INSTRUCTIONS FOR REGISTRATION OF STOCK (Please typewrite or print in block
letters)

Name:       _________________________________________________________


Address:    _________________________________________________________
            _________________________________________________________
            _________________________________________________________

Signature:  _________________________________________________________