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                                                                   EXHIBIT 10.15

THIS WARRANT HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
AMENDED (THE "1933 ACT"), OR ANY APPLICABLE STATE SECURITIES LAWS, AND. MAY NOT
BE SOLD OR TRANSFERRED UNLESS SUCH SALE OR TRANSFER IS IN ACCORDANCE WITH THE
REGISTRATION REQUIREMENTS OF SUCH ACT AND APPLICABLE LAWS OR SOME OTHER
EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF SUCH ACT AND APPLICABLE LAWS IS
AVAILABLE WITH RESPECT THERETO.

                        PREFERRED STOCK PURCHASE WARRANT

Warrant No. W-1                                        Number of Shares: 400,000
                                   Series E-1 Voting Convertible Preferred Stock
                                                         (subject to adjustment)

                                NEUROMETRIX, INC.

                          Effective as of May 21, 2003

                             Void after May 21, 2010

     1.     ISSUANCE. This Preferred Stock Purchase Warrant (the "WARRANT") is
issued to LIGHTHOUSE CAPITAL PARTNERS IV, L.P. by NEUROMETRIX INC, a Delaware
corporation (hereinafter with its successors called the "COMPANY").

     2.     PURCHASE PRICE; NUMBER OF SHARES.

            (a)    The registered holder of this Warrant (the "HOLDER"),
commencing on the date hereof, is entitled upon surrender of this Warrant with
the subscription form annexed hereto duly executed, at the principal office of
the Company, to purchase from the Company, at a price per share of $1.50 (the
"PURCHASE PRICE"), 400,000 fully paid and nonassessable shares of the Company's
Series E-1 Voting Convertible Preferred Stock, $0.001 par value (the "Preferred
Stock").

            (b)    On December 31, 2003, the number of shares of Preferred Stock
issuable upon the exercise of this Warrant (the "EXERCISE QUANTITY") shall
automatically and without further action on the part of the Company or the
Holder be reduced to 333,333 shares in the event Company has drawn $2,000,000 or
less of the Commitment Amount under the Loan Agreement.

     In addition to other terms which may be defined herein, the following
terms, as used in this Warrant, shall have the following meanings:

                   (i)    "Commitment Amount " means $3,000,000.00.

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                   (ii)   "Loan Agreement" means that certain Loan and Security
     Agreement No. 3561 dated May 21, 2003 between the Company and Lighthouse
     Capital Partners IV, L.P..

     Any term not defined herein shall have the meaning as set forth in the Loan
     Agreement.

     Until such time as this Warrant is exercised in full or expires, the
Purchase Price and the securities issuable upon exercise of this Warrant are
subject to adjustment as hereinafter provided. The person or persons in whose
name or names any certificate representing shares of Preferred Stock is issued
hereunder shall be deemed to have become the holder of record of the shares
represented thereby as at the close of business on the date this Warrant is
exercised with respect to such shares, whether or not the transfer books of the
Company shall be closed.

     3.     PAYMENT OF PURCHASE PRICE. The Purchase Price may be paid (i) in
cash or by check, (ii) by the surrender by the Holder to the Company of any
promissory notes or other obligations issued by the Company, with all such notes
and obligations so surrendered being credited against the Purchase Price in an
amount equal to the principal amount thereof plus accrued interest to the date
of surrender, or (iii) by any combination of the foregoing.

     4.     NET ISSUE ELECTION. The Holder may elect to receive, without the
payment by the Holder of any additional consideration, shares of Preferred Stock
equal to the value of this Warrant or any portion hereof by the surrender of
this Warrant or such portion to the Company, with the net issue election notice
annexed hereto duly executed, at the principal office of the Company. Thereupon,
the Company shall issue to the Holder such number of fully paid and
nonassessable shares of Preferred Stock as is computed using the following
formula:

                                   X - Y(A-B)
                                       ------
                                         A

     where:    X  =  the number of shares of Preferred Stock to be issued to the
                     Holder pursuant to this SECTION 4.

               Y  =  the number of shares of Preferred Stock covered by this
                     Warrant in respect of which the net issue election is made
                     pursuant to this SECTION 4.

               A  =  the Fair Market Value (defined below) of one share of
                     Preferred Stock, as determined at the time the net issue
                     election is made pursuant to this SECTION 4.

               B  =  the Purchase Price in effect under this Warrant at the time
                     the net issue election is made pursuant to this SECTION 4.

     "FAIR MARKET VALUE" of a share of Preferred Stock (or fully paid and
nonassessable shares of the Company's common stock, $0.0001 par value (the
"COMMON STOCK") if the Preferred Stock has been automatically converted into
Common Stock) as of the date that the net issue election is made (the
"DETERMINATION DATE") shall mean:

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                   (i)    If the net issue election is made in connection with
     and contingent upon the closing of the sale of the Company's Common Stock
     to the public in a public offering pursuant to a Registration Statement
     under the 1933 Act (a "PUBLIC OFFERING"), and if the Company's Registration
     Statement relating to such Public Offering ("REGISTRATION STATEMENT") has
     been declared effective by the Securities and Exchange Commission, then the
     initial "Price to Public" specified in the final prospectus with respect to
     such offering multiplied by the number of shares of Common Stock into which
     each share of Preferred Stock is then convertible.

                   (ii)   If the net issue election is not made in connection
     with and contingent upon a Public Offering, then as follows:

                          (A)   If traded on a securities exchange or the Nasdaq
            National Market, the fair market value of the Common Stock shall be
            deemed to be the average of the closing or last reported sale prices
            of the Common Stock on such exchange or market over the five day
            period ending five trading days prior to the Determination Date, and
            the fair market value of the Preferred Stock shall be deemed to be
            such fair market value of the Common Stock multiplied by the number
            of shares of Common Stock into which each share of Preferred Stock
            is then convertible;

                          (B)   If otherwise traded in an over-the-counter
            market, the fair market value of the Common Stock shall be deemed to
            be the average of the closing ask prices of the Common Stock over
            the five day period ending five trading days prior to the
            Determinations Date, and the fair market value of the Preferred
            Stock shall be deemed to be such fair market value of the Common
            Stock multiplied by the number of shares of Common Stock into which
            each share of Preferred Stock is then convertible; and

                          (C)   If there is no public market for the Common
            Stock, then fair market value shall be determined in good faith by
            the Company's Board of Directors.

     5.     PARTIAL EXERCISE. This Warrant may be exercised in part, and the
Holder shall be entitled to receive a new warrant, which shall be dated as of
the date of this Warrant, covering the number of shares in respect of which this
Warrant shall not have been exercised.

     6.     FRACTIONAL SHARES. In no event shall any fractional share of
Preferred Stock be issued upon any exercise of this Warrant. If, upon exercise
of this Warrant in its entirety, the Holder would, except as provided in this
Section 6, be entitled to receive a fractional share of Preferred Stock, then
the Company shall issue the next higher number of full shares of Preferred
Stock, issuing a full share with respect to such fractional share.

     7.     EXPIRATION DATE; AUTOMATIC EXERCISE. This Warrant shall expire at
the close of business on the earlier to occur of (i) May 21, 2010, or (ii) two
years after the closing of the initial Public Offering; of the Company on the
NASDAQ or other stock exchange in the United States, and shall be void
thereafter (the "EXPIRATION DATE").

                                        3
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     Notwithstanding the term of this Warrant fixed pursuant to this Section 7,
and provided Holder has received advance written notice of at least twenty (20)
days and has not earlier exercised this Warrant, and provided this Warrant has
not been assumed by the successor entity (or parent thereof), upon the
consummation of a Merger (as defined below), this Warrant shall automatically be
exercised pursuant to Section 4 hereof, without any action by Holder. "MERGER"
means: (i) a sale of all or substantially all of the Company's assets to an
Unaffiliated Entity (as defined below), or (ii) the merger, consolidation or
acquisition of the Company with, into or by an Unaffiliated Entity (other than a
merger or consolidation for the principle purpose of changing the domicile of
the Company or a bona fide round of preferred stock equity financing), that
results in the transfer of fifty percent (50%) or more of the outstanding voting
power of the Company. "UNAFFILIATED ENTITY" means any entity that is owned or
controlled by parties who own less than twenty percent (20%) of the combined
voting power of the voting securities of the Company immediately prior to such
merger, consolidation or acquisition. The Company agrees to promptly give the
Holder written notice of any proposed Merger and written notice of termination
of any proposed Merger. Notwithstanding anything to the contrary in this
Warrant, the Holder may rescind any exercise of its purchase rights after a
notice of termination of the proposed Merger if the exercise of this Warrant
occurred after the Company notified the Holder that the Merger was proposed or
if the exercise was otherwise precipitated by such proposed Merger, provided,
however that such rescission right must be exercised within thirty (30) days of
receipt of such written notice of termination of the proposed Merger. In the
event of such rescission, this Warrant will continue to be exercisable on the
same terms and conditions.

     8.     RESERVED SHARES; VALID ISSUANCE. The Company covenants that it will
at all times from and after the date hereof reserve and keep available such
number of its authorized shares of Preferred Stock and Common Stock free from
all preemptive or similar rights therein, as will be sufficient to permit,
respectively, the exercise of this Warrant in full and the conversion into
shares of Common Stock of all shares of Preferred Stock receivable upon such
exercise. The Company further covenants that such shares as may be issued
pursuant to such exercise and/or conversion will, upon issuance, be duly and
validly issued, fully paid and nonassessable and free from all taxes, liens and
charges with respect to the issuance thereof.

     9.     STOCK SPLITS AND DIVIDENDS. If after the date hereof the Company
shall subdivide the Preferred Stock, by split-up or otherwise, or combine the
Preferred Stock, or issue additional shares of Preferred Stock in payment of a
stock dividend on the Preferred Stock, the number of shares of Preferred Stock
issuable on the exercise of this Warrant shall forthwith be proportionately
increased in the case of a subdivision or stock dividend, or proportionately
decreased in the case of a combination, and the Purchase Price shall forthwith
be proportionately decreased in the cast of a subdivision or stock dividend, or
proportionately increased in the case of a combination.

     10.    ADJUSTMENTS FOR DILUTING ISSUANCES. The other antidilution rights
applicable to the Preferred Stock and the Common Stock of the Company are set
forth in the Amended and Restated Certificate of Incorporation, as amended from
time to time (the "ARTICLES"), a true and complete copy in its current form
which is attached hereto as EXHIBIT A. Such rights shall not be restated,
amended or modified in any manner which affects the Holder differently than the
holders of Series E-1 Preferred without such Holder's prior written consent The
Company shall

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promptly provide the Holder hereof with any restatement, amendment or
modification to the Articles promptly after the same has been made.

     11.    MERGERS AND RECLASSIFICATIONS. Except in connection with an exercise
under SECTION 7, if after the date hereof the Company shall enter into any
Reorganization (as hereinafter defined), then, as a condition of such
Reorganization, lawful provisions shall be made, and duly executed documents
evidencing the same from the Company or its successor shall be delivered to the
Holder, so that the Holder shall thereafter have the right to purchase, at a
total price not to exceed that payable upon the exercise of this Warrant in
full, the kind and amount of shares of stock and other securities and property
receivable upon such Reorganization by a holder of the number of shares of
Preferred Stock which might have been purchased by the Holder immediately prior
to such Reorganization, and in any such case appropriate provisions shall be
made with respect to the rights and interest of the Holder to the end that the
provisions hereof (including without limitation, provisions for the adjustment
of the Purchase Price and the number of shares issuable hereunder and the
provisions relating to the net issue election) shall thereafter be applicable in
relation to any shares of stock or other securities and property thereafter
deliverable upon exercise hereof. For the purposes of this SECTION 11, the term
"REORGANIZATION" shall include without limitation any reclassification, capital
reorganization or change of the Preferred Stock (other than as a result of a
subdivision, combination or stock dividend provided for in SECTION 9 hereof), or
any consolidation of the Company with, or merger of the Company into, another
corporation or other business organization (other than a merger in which the
Company is the surviving corporation and which does not result in any
reclassification or change of the outstanding Preferred Stock), or any sale or
conveyance to another corporation or other business organization of all or
substantially all of the assets of the Company.

     12.    CERTIFICATE OF ADJUSTMENT. Whenever the Purchase Price is adjusted,
as herein provided, the Company shall promptly deliver to the Holder a
certificate of the Company's chief financial officer setting forth the Purchase
Price after such adjustment and setting forth a brief statement of the facts
requiring such adjustment.

     13.    NOTICES OF RECORD DATE, ETC. In the event of:

            (a)    any taking by the Company of a record of the holders of any
class of securities for the purpose of determining the holders thereof who are
entitled to receive any dividend or other distribution, or any statutory right
to subscribe for, purchase, sell or otherwise acquire or dispose of any shares
of stock of any class or any other securities or property, or to receive any
other right;

            (b)    any reclassification of the capital stock of the Company,
capital reorganization of the Company, consolidation or merger involving the
Company, or sale or conveyance of all or substantially all of its assets; or

            (c)    any voluntary or involuntary dissolution, liquidation or
winding-up of the Company;

                                        5
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then in each such event the Company will provide or cause to be provided to the
Holder a written notice thereof. Such notice shall be provided at least twenty
(20) business days prior to the date specified in such notice on which any such
action is to be taken.

     14.    REPRESENTATIONS, WARRANTIES AND COVENANTS. This Warrant is issued
and delivered by the Company and accepted by each Holder on the basis of the
following representations, warranties and covenants made by the Company:

            (a)    The Company has all necessary authority to issue, execute and
deliver this Warrant and to perform its obligations hereunder. This Warrant has
been duly authorized issued, executed and delivered by the Company and is the
valid and binding obligation of the Company, enforceable in accordance with its
terms.

            (b)    The shares of Preferred Stock issuable upon the exercise of
this Warrant have been duly authorized and reserved for issuance by the Company
and, when issued in accordance with the teams hereof, will be validly issued,
fully paid and nonassessable.

            (c)    The issuance, execution and delivery of this Warrant do not,
and the issuance of the shares of Preferred Stock upon the exercise of this
Warrant in accordance with the terms hereof will not, (i) violate or contravene
the Company's Articles or by-laws, or any law, statute, regulation, rule,
judgment or order applicable to the Company, (ii) violate, contravene or result
in a breach of default under any contract, agreement or instrument to which the
Company is a party or by which the Company or any of its assets are bound or
(iii) require the consent or approval of or the filing of any notice or
registration with any person or entity except for such consents or approvals as
have been obtained as of the date hereof.

            (d)    So long as this Warrant has not terminated or any shares of
Preferred Stock issued upon exercise of this Warrant are outstanding, Holder
shall be entitled to receive such financial and other information as the Holder
would be entitled to receive under the Stock Purchase Agreement applicable to
the Preferred Stock issuable hereunder without regard or limitation with respect
to minimum holdings of Preferred Stock.

            (e)    As of the date hereof, the authorized capital stock of the
Company consists of (i) 30,000,000 shares of Common Stock, par value $0.0001 per
share, of which 4,137,208 shares are issued and outstanding and 23,589,151
shares have been reserved for issuance upon conversion of Preferred Stock
(including 400,000 shares reserved for issuance upon conversion of shares of
Series E-1 Voting Convertible Preferred Stock issuable upon exercise of this
Warrant with respect to Preferred Stock or for issuance upon exercise of this
Warrant with respect to Common Stock) and (ii) 21,164,763 shares of Preferred
Stock, par value $0.001 per share, of which (A) 875,000 shares have been
designated as Series A Voting Convertible Preferred Stock, all of which shares
are issued and outstanding, (B) 625,000 shares have been designated as Series B
Voting Convertible Preferred Stock, all of which shares are issued and
outstanding, (C) 2,850,000 shares have been designated as Series C-1 Voting
Convertible Preferred Stock, all of which shares are issued and outstanding, (D)
1,148,100 shares have been designated as Series C-2 Non Voting Convertible
Preferred Stock, all of which shares are issued and outstanding, (E) 6,222,220
shares have been designated as Series D Voting Convertible Preferred Shock, all
of which shares are issued or outstanding, (F) 7,111,110 shares have been

                                        6
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designated as Series E Voting Convertible Preferred Stock, of which 4,444,445
shares are issued and outstanding, and (G) 2,333,334 shares have been designated
as Series E-1 Voting Convertible Preferred Stock, of which 1,333,334 shares are
issued and outstanding and 400,000 shares have been reserved for issuance upon
exercise of this Warrant Attached hereto as EXHIBIT B is a capitalization table
summarizing the capitalization of the Company. Once per calendar quarter, the
Company will provide Holder with a current capitalization table indicating
changes, if any, to the number of outstanding shares of common stock and
preferred stock.

     15.    REGISTRATION RIGHTS. The Company hereby grants to the Holder, on a
pari passu basis with all other parties thereto, all the registration and
related rights of a "holder of Registrable Shares" under Section 9 of that
certain Series E-1 Convertible Preferred Stock Purchase Agreement, dated as of
December 20, 2002, as amended from time to time, among the Company and the other
parties thereto (the "RIGHTS AGREEMENT"), and agrees that any and all shares of
Common Stock held by the Holder issued or issuable upon conversion of the shares
of Preferred Stock issued or issuable upon the exercise of this Warrant (or, if
this Warrant becomes a warrant to purchase shares of Common Stock, Common Stock
issued or issuable upon the exercise of this Warrant) shall be "Registrable
Shares" within the meaning of the Rights Agreement. The Holder agrees to comply
with all obligations of a holder of Registrable Shares under the provisions of
the Rights Agreement, including without limitation the "Lock-Up" and Market
Standstill provisions in Section 9.13 of the Rights Agreement.

     16.    AMENDMENT. The terms of this Warrant may be amended, modified or
waived only with the written consent of the Holder and the Company.

     17.    REPRESENTATIONS AND COVENANTS OF THE HOLDER. This Warrant has been
entered into by the Company in reliance upon the following representations and
covenants of the Holder, which by its execution hereof the Holder hereby
confirms:

            (a)    INVESTMENT PURPOSE. The right to acquire Preferred Stock or
the Preferred Stock issuable upon exercise of the Holder's rights contained
herein will be acquired for investment and not with a view to the sale or
distribution of any part thereof, and the Holder has no present intention of
selling or engaging in any public distribution of the same except pursuant to a
registration or exemption.

            (b)    ACCREDITED INVESTOR. Holder is an "accredited investor'"
within the meaning of the Securities and Exchange Rule 501 of Regulation D, as
presently in effect.

            (c)    PRIVATE ISSUE. The Holder understands (i) that the Preferred
Stock issuable upon exercise of the Holder's rights contained herein is not
registered under the 1933 Act or qualified under applicable state securities
laws on the ground that the issuance contemplated by this Warrant will be exempt
from the registration and qualifications requirements thereof; and (ii) that the
Company's reliance on such exemption is predicated on the representations set
forth in this Section 17.

            (d)    SUITABILITY. The Holder confirms that the Holder understands
and has fully considered for purposes of this investment the risks of this
investment and understands that (i) this investment is suitable only for an
investor which is able to bear the economic

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consequences of losing its entire investment; (ii) the Company is an early-stage
enterprise with limited operating history, and limited revenues and no net
income from operations to date; (iii) the purchase of the Warrant and the
purchase of the shares of Preferred Stock issuable on exercise of this Warrant
is a speculative investment which involves a high degree of risk of loss of the
entire investment; and (iv) there are substantial restrictions on the
transferability of, and there will be no public market for, the shares of
Preferred Stock, and accordingly, it may not be possible for the Holder to
liquidate its investment.

            (e)    LACK OF LIQUIDITY. The Holder confirms that it is able (i) to
bear the economic risk of this investment (ii) to hold the Warrant and any
shares of Preferred Stock purchased by the Holder hereunder for an indefinite
period of time, and (iii) presently to afford a complete loss of the Holder's
investment.

            (f)    FINANCIAL RISK. The Holder has such knowledge and experience
in financial and business matters as to be capable of evaluating the merits and
risks of its investment and has the ability to bear the economic risks of its
investment.

            (g)    ACCESS TO MANAGEMENT. The Holder confirms that, in making the
Holder's decision to acquire the Warrant or purchase shares of Preferred Stock
(or Common Stock) pursuant to the Warrant, the Holder has relied solely upon
independent investigations made by the Holder, and that the Holder has been
given the opportunity to ask questions of, and to receive answers from,
management or other persons acting on behalf of the Company concerning the
Company and the terms and conditions of this investment, and to obtain any
additional information, to the extent such persons possess such information

            (h)    JURISDICTION OF ORGANIZATION.  The Holder has its principal
place of business in the State of California.

            (i)    AUTHORITY. The Holder has full power and authority to
execute, deliver and perform the Warrant in accordance with its terms. The
Holder has not been organized, reorganized, or recapitalized specifically for
the purpose of investing in the Company.

     18.    NOTICES, TRANSFERS, ETC.

            (a)    Any notice or written communication required or permitted to
be given to the Holder may be given by certified mail or delivered to the Holder
at the address most recently provided by the Holder to the Company.

            (b)    Subject to compliance with applicable federal and state
securities laws, this Warrant may be transferred by the Holder with respect to
(i) an affiliate, any or all of the shares purchasable hereunder, and (ii) with
respect to a person that is not an affiliate, all, but not less than all of the
shares purchasable hereunder, provided such transferee is not a competitor of
the Company or an affiliate of such a competitor. Upon surrender of this Warrant
to the Company, together with (i) the assignment notice annexed hereto duly
executed, for transfer of this Warrant in whole or in part by the Holder, (ii)
an executed assignment and assumption agreement whereby the transferee agrees to
be bound by all the terms of this Warrant, (iii) a certificate of the transferee
representing to the Company that the representations and warranties of the
Holder in SECTION 16 are true and correct with respect the transferee as of the
date of

                                        8
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transfer, and (iv) if requested by the Company or its transfer agent, a legal
opinion addressed to the Company concluding that the transfer is exempt from the
registration requirements of the Securities Act of 1933, as amended, the Company
shall issue a new warrant of the same denomination to the assignee. Upon
surrender of this Warrant to the Company, together with the assignment hereof
properly endorsed by the Holder for transfer with respect to a portion of the
shares of Preferred Stock purchasable hereunder, the Company shall issue a new
warrant to the assignee, in such denomination as shall be requested by the
Holder hereof, and shall issue to such Holder a new warrant covering the number
of shares in respect of which this Warrant shall not have been transferred.

            (c)    In case this Warrant shall be mutilated, lost, stolen or
destroyed the Company shall issue a new warrant of like tenor and denomination
and deliver the same (i) in exchange and substitution for and upon surrender and
cancellation of any mutilated Warrant, or (it) in lieu of any Warrant lost,
stolen or destroyed, upon receipt of an affidavit of the Holder and indemnity
reasonably acceptable to the Company and other evidence reasonably satisfactory
to the Company of the loss, theft or destruction of such Warrant.

     19.    GOVERNING LAW. The provisions and terms of this Warrant shall be
governed by and construed in accordance with the internal laws of the State of
Delaware without giving effect to its principles regarding conflicts of laws.

     20.    SUCCESSORS AND ASSIGNS. This Warrant shall be binding upon the
Company's successors and assigns and shall inure to the benefit of the Holder's
successors, legal representatives and permitted assigns.

     21.    BUSINESS DAYS. If the last or appointed day for the taking of any
action required or the expiration of any rights granted herein shall be a
Saturday or Sunday or a legal holiday in California, then such action may be
taken or right may be exercised on the next succeeding day which is not a
Saturday or Sunday or such a legal holiday.

     22.    CONVERSION TO COMMON STOCK WARRANT. If, for any reason, all
outstanding shares of Preferred Stock are converted into shares of Common Stock
prior to the exercise in full of this Warrant (a "Common Stock Conversion"),
then, effective upon such conversion, this Warrant shall automatically and
without any further action on the part of the Company or the Holder become a
Warrant for the purchase of shares of Common Stock. The Holder shall thereupon
have the right to purchase that number of shares of Common Stock equal to the
number of shares of Common Stock which would have been receivable by the Holder
if the Holder had exercised this Warrant for shares of Preferred Stock
immediately prior to the Common Stock Conversion and had participated in the
Common Stock Conversion (the "Common Stock Number"), at a price per share of
Common Stock equal to (x) the total, price payable upon the exercise of this
Warrant in full, divided by (y) the Common Stock Number. In such event
appropriate provisions shall be made with respect to the rights and interest of
the Holder to the end that the provisions hereof (including, without limitation,
the provisions for the adjustment of the Purchase Price and of the number of
shares purchasable upon exercise of this Warrant) shall thereafter be applicable
to any shares of Common Stock deliverable upon the exercise hereof.

                                        9
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     23.    VALUE. The Company and the Holder agree that the value of this
Warrant on the date of grant is $100.

Dated:  May 21, 2003

                                              NEUROMETRIX, INC.


                                              By: /s/ Shai N. Gozani
                                                 --------------------

                                              Name: Shai N. Gozani

                                              Title: President and CEO

                                       10
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                                  SUBSCRIPTION

To: ___________________


Date: _________________

The undersigned hereby subscribes for ______ shares of Preferred Stock covered
by this Warrant. The certificate(s) for such shares shall be issued in the name
of the undersigned or as otherwise indicated below:


                                              ----------------------------------
                                              Signature


                                              ----------------------------------
                                              Name for Registration


                                              ----------------------------------
                                              Mailing Address

                                       11
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                            NET ISSUE ELECTION NOTICE

To: ___________________                                  Date: _________________


The undersigned hereby elects under SECTION 4 to surrender the right to purchase
shares of Preferred Stock pursuant to this Warrant. The certificate(s) for such
shares issuable upon such net issue election shall be issued in the name of the
undersigned or as otherwise indicated below:


                                              ----------------------------------
                                              Signature


                                              ----------------------------------
                                              Name for Registration


                                              ----------------------------------
                                              Mailing Address

                                       12
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                                   ASSIGNMENT

For value received ____________ hereby sells, assigns and transfers unto
________________ [Please print or typewrite name and address of Assignee] the
within Warrant, and does hereby irrevocably constitute and appoint ____________
its attorney to transfer the within Warrant on the books of the within named
Company with full power of substitution on the premises.

                                              Dated:
                                                    ----------------------------


                                              ----------------------------------
                                              Signature


                                              ----------------------------------
                                              Name for Registration


                                              In the Presence of:


                                              ----------------------------------

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