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                                                                    EXHIBIT 10.6

                                NEUROMETRIX, INC.
                        2004 EMPLOYEE STOCK PURCHASE PLAN

     1.   PURPOSE. The purpose of the NeuroMetrix, Inc. 2004 Employee Stock
Purchase Plan (the "Plan") is to provide eligible employees of NeuroMetrix, Inc.
(the "Company") or a Designated Subsidiary (as defined in Section 11) with
opportunities to purchase shares of the Company's common stock, par value
$0.0001 per share (the "Common Stock"). One million five hundred thousand
(1,500,000) shares of Common Stock in the aggregate have been approved and
reserved for this purpose. The Plan is intended to constitute an "employee stock
purchase plan" within the meaning of Section 423(b) of the Internal Revenue Code
of 1986, as amended (the "Code"), and shall be interpreted in accordance with
that intent.

     2.   ADMINISTRATION. The Plan will be administered by the person or persons
(the "Administrator") appointed by the Company's Board of Directors (the
"Board") for such purpose. The Administrator has authority to make rules and
regulations for the administration of the Plan, and its interpretations and
decisions with regard thereto shall be final and conclusive. No member of the
Board or individual exercising administrative authority with respect to the Plan
shall be liable for any action or determination made in good faith with respect
to the Plan or any option granted hereunder.

     3.   OFFERINGS. The Company will make one or more offerings to Eligible
Employees (as defined below) to purchase Common Stock under the Plan
("Offerings"). Unless otherwise determined by the Administrator, the initial
Offering will begin on the Effective Date and will end on the following December
31 (the "Initial Offering"). Thereafter, unless otherwise determined by the
Administrator, an Offering will begin on the first business day occurring on or
after each January 1 and July 1 and will end on the last business day occurring
on or before the following June 30 and December 31, respectively. The
Administrator may, in its discretion, designate a different period for any
Offering, provided that no Offering shall exceed 27 months in duration or
overlap any other Offering.

     4.   ELIGIBILITY. Each individual classified as an employee (within the
meaning of Section 3401(c) of the Code and the regulations thereunder) by the
Company or a Designated Subsidiary on the Company's or the Designated
Subsidiary's payroll records during the relevant participation period (each an
"Eligible Employee") is eligible to participate in any one or more of the
Offerings under the Plan, provided that as of the first day of the applicable
Offering (the "Offering Date") they are customarily employed by the Company or a
Designated Subsidiary for more than 20 hours a week and more than five months in
the calendar year during which the Offering Date occurs or in the calendar year
immediately preceding such year, and have completed at least 60 days of
employment.

     5.   PARTICIPATION.

     (a)  PARTICIPANTS ON EFFECTIVE DATE. Each Eligible Employee on the
Effective Date shall be deemed to be a Participant at such time. If an Eligible
Employee is deemed to be a Participant pursuant to this Section 5(a), he shall
be deemed not to have authorized payroll deductions and shall not purchase any
Common Stock hereunder unless he thereafter authorizes

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payroll deductions (in the manner described in Section 5(b)) by the end of the
first Offering. If such a Participant does not authorize payroll deductions by
the end of the first Offering, that Participant will be deemed to have withdrawn
from the Plan.

     (b)  PARTICIPANTS IN SUBSEQUENT OFFERINGS. Any Eligible Employee who is not
a Participant may elect to become a Participant by submitting an enrollment form
to his appropriate payroll location at least 15 business days before the
Offering Date (or such other deadline as shall be established by the
Administrator for the Offering). The form will (i) state a whole percentage at a
minimum of one percent (1%) and a maximum of ten percent (10%) to be deducted
from his Compensation (as defined in Section 11) per pay period, (ii) authorize
the purchase of Common Stock for him in each Offering in accordance with the
terms of the Plan and (iii) specify the exact name or names in which shares of
Common Stock purchased for him are to be issued pursuant to Section 10. The
Company will maintain book accounts showing the amount of payroll deductions
made by each Participant for each Offering. No interest will accrue or be paid
on payroll deductions. An employee who does not enroll in accordance with these
procedures will be deemed to have waived his right to participate.

     (d)  Except as provided elsewhere in the Plan, a Participant's election to
participate in the Plan and payroll deduction election shall continue in effect
until the Participant withdraws from the Plan or terminates employment.

     (e)  All Participants shall have the same rights and privileges under the
Plan, except for differences that may be mandated by local law and that are
consistent with Code Section 423(b)(5).

     (f)  In accordance with Section 423(b)(8) of the Code, the Committee may
reduce a Participant's payroll deductions to zero percent (0%) at any time
during an Offering.

     6.   DEDUCTION CHANGES. Except in the event of a Participant increasing his
payroll deduction from 0% during the Initial Offering (as specified in Section
5(a)) or as may be determined by the Administrator in advance of an Offering, a
Participant may not increase or decrease his payroll deduction during any
Offering, but may increase or decrease his payroll deduction with respect to the
next Offering (subject to the limitations of Section 5) by filing a new
enrollment form at least 15 business days before the next Offering Date (or by
such other deadline as shall be established by the Administrator for the
Offering). The Administrator may, in advance of any Offering, establish rules
permitting an employee to increase, decrease or terminate his payroll deduction
during an Offering.

     7.   WITHDRAWAL. A Participant may withdraw from participation in the Plan
by delivering a written notice of withdrawal to his appropriate payroll
location. The Participant's withdrawal will be effective as of the next business
day. Following a Participant's withdrawal, the Company will promptly refund to
him his entire account balance under the Plan (after payment for any Common
Stock purchased before the effective date of withdrawal). Partial withdrawals
are not permitted. The employee may not begin participation again during the
remainder of the Offering, but may enroll in a subsequent Offering in accordance
with Section 5.

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     8.   GRANT OF OPTIONS. On each Offering Date, the Company will grant to
each Participant an option ("Option") to purchase on the last day of such
Offering (the "Exercise Date"), at the Option Price hereinafter provided for,
(a) a number of shares of Common Stock determined by the Administrator in
advance of an Offering either (i) by dividing such employee's accumulated
payroll deductions on such Exercise Date by the lower of (x) the Applicable
Percentage (as defined in Section 11) of the Fair Market Value of the Common
Stock on the Offering Date, or (y) the Applicable Percentage of the Fair Market
Value of the Common Stock on the Exercise Date, or (ii) by dividing such
employee's accumulated payroll deductions on such Exercise Date by the
Applicable Percentage of the Fair Market Value of the Common Stock on the
Exercise Date, or (b) such other lesser maximum number of shares as shall have
been established by the Administrator in advance of the Offering; provided,
however, that such Option shall be subject to the limitations set forth below.
Each employee's Option shall be exercisable only to the extent of such
employee's accumulated payroll deductions on the Exercise Date. The purchase
price for each share purchased under each Option (the "Option Price") will be
the Applicable Percentage of the Fair Market Value of the Common Stock as
determined by the Administrator in advance of an Offering either (a) on the
Offering Date or the Exercise Date, whichever is less or (b) on the Exercise
Date.

     Notwithstanding the foregoing, no employee may be granted an option
hereunder if such employee, immediately after the option was granted, would be
treated as owning stock possessing five percent (5%) or more of the total
combined voting power or value of all classes of stock of the Company or any
Parent or Subsidiary (as defined in Section 11). For purposes of the preceding
sentence, the attribution rules of Section 424(d) of the Code shall apply in
determining the stock ownership of an employee, and all stock which the employee
has a contractual right to purchase shall be treated as stock owned by the
employee. In addition, no employee may be granted an Option which permits his
rights to purchase stock under the Plan, and any other employee stock purchase
plan of the Company and its Parents and Subsidiaries, to accrue at a rate which
exceeds $25,000 of the fair market value of such stock (determined on the option
grant date or dates) for each calendar year in which the Option is outstanding
at any time. The purpose of the limitation in the preceding sentence is to
comply with Section 423(b)(8) of the Code and shall be applied taking Options
into account in the order in which they were granted.

     9.   EXERCISE OF OPTION AND PURCHASE OF SHARES. Each employee who continues
to be a Participant in the Plan on the Exercise Date shall be deemed to have
exercised his Option on such date and shall acquire from the Company such number
of whole shares of Common Stock reserved for the purpose of the Plan as his
accumulated payroll deductions on such date will purchase at the Option Price,
subject to any other limitations contained in the Plan. Any amount remaining in
a Participant's account at the end of an Offering solely by reason of the
inability to purchase a fractional share will be carried forward to the next
Offering; any other balance remaining in a Participant's account at the end of
an Offering will be refunded to the employee promptly.

     10.  ISSUANCE OF CERTIFICATES. Certificates representing shares of Common
Stock purchased under the Plan may be issued only in the name of the employee,
in the name of the employee and another person of legal age as joint tenants
with rights of survivorship, or in the name of a broker authorized by the
employee to be his, or their, nominee for such purpose.

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     11.  DEFINITIONS.

          (a)  The term "Applicable Percentage" means 85% (or such higher
percentage as may be determined by the Administrator in advance of an Offering).

          (b)  The term "Compensation" means the amount of base pay and
commissions, prior to salary reduction pursuant to Sections 125, 132(f) or
401(k) of the Code, but excluding overtime, incentive or bonus awards,
allowances and reimbursements for expenses such as relocation allowances or
travel expenses, income or gains on the exercise of Company stock options, and
similar items.

          (c)  The term "Designated Subsidiary" means any present or future
Subsidiary (as defined below) that has been designated by the Board to
participate in the Plan. The Board may so designate any Subsidiary, or revoke
any such designation, at any time and from time to time, either before or after
the Plan is approved by stockholders.

          (d)  The term "Effective Date" means the date of the Initial Public
Offering.

          (e)  The term "Fair Market Value of the Common Stock" on any given
date means the fair market value of the Common Stock determined in good faith by
the Administrator; provided, however, that if the Common Stock is traded on The
NASDAQ National Market or a national securities exchange, the Fair Market Value
of the Common Stock will equal the closing sales price as reported on the
principal exchange or market for the Common Stock on such date. If there is no
trading on such date, the determination shall be made by reference to the last
date preceding such date for which there was trading. Notwithstanding the
foregoing, if the date for which Fair Market Value of the Common Stock is
determined is the first day when trading prices for the Common Stock are
reported on The NASDAQ National Market or on a national securities exchange, the
Fair Market Value of the Common Stock shall be the "Price to the Public" (or
equivalent) set forth on the cover page for the final prospectus relating to the
Company's Initial Public Offering.

          (f)  The term "Initial Public Offering" means the consummation of the
first fully underwritten, firm commitment public offering pursuant to an
effective registration statement under the Securities Act of 1933, as amended,
covering the offer and sale by the Company of its Common Stock.

          (g)  The term "Parent" means a "parent corporation" with respect to
the Company, as defined in Section 424(e) of the Code.

          (h)  The term "Participant" means an Eligible Employee who has
complied with the provisions of Section 5.

          (i)  The term "Subsidiary" means a "subsidiary corporation" with
respect to the Company, as defined in Section 424(f) of the Code.

     12.  RIGHTS ON TERMINATION OF EMPLOYMENT. If a Participant's employment
terminates for any reason before the Exercise Date for any Offering, no payroll
deduction will be taken from any pay due and owing to the employee and the
balance in his account will be paid to him

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or, in the case of his death, to his designated beneficiary as if he had
withdrawn from the Plan under Section 7. An employee will be deemed to have
terminated employment, for this purpose, if the corporation that employs him,
having been a Designated Subsidiary, ceases to be a Subsidiary, or if the
employee is transferred to any corporation other than the Company or a
Designated Subsidiary. An employee will not be deemed to have terminated
employment, for this purpose, if the employee is on an approved leave of absence
for military service or sickness, or for any other purpose approved by the
Company, if the employee's right to reemployment is guaranteed either by a
statute or by contract or under the policy pursuant to which the leave of
absence was granted or if the Administrator otherwise provides in writing.

     13.  SPECIAL RULES. Notwithstanding anything herein to the contrary, the
Administrator may adopt special rules applicable to the employees of a
particular Designated Subsidiary, whenever the Administrator determines that
such rules are necessary or appropriate for the implementation of the Plan in a
jurisdiction where such Designated Subsidiary has employees; provided that such
rules are consistent with the requirements of Section 423(b) of the Code. Such
special rules may include (by way of example, but not by way of limitation) the
establishment of a method for employees of a given Designated Subsidiary to fund
the purchase of shares other than by payroll deduction, if the payroll deduction
method is prohibited by local law or is otherwise impracticable. Any special
rules established pursuant to this Section 13 shall, to the extent possible,
result in the employees subject to such rules having substantially the same
rights as other Participants in the Plan.

     14.  OPTIONEES NOT STOCKHOLDERS. Neither the granting of an Option to an
employee nor the deductions from his pay shall constitute such employee a holder
of the shares of Common Stock covered by an Option under the Plan until such
shares have been purchased by and issued to him.

     15.  RIGHTS NOT TRANSFERABLE. Rights under the Plan are not transferable by
a participating employee other than by will or the laws of descent and
distribution, and are exercisable during the employee's lifetime only by the
employee.

     16.  APPLICATION OF FUNDS. All funds received or held by the Company under
the Plan may be combined with other corporate funds and may be used for any
corporate purpose.

     17.  ADJUSTMENT IN CASE OF CHANGES AFFECTING COMMON STOCK. In the event of
a subdivision of outstanding shares of Common Stock, or the payment of a
dividend in Common Stock, the number of shares approved for the Plan, and the
share limitation set forth in Section 8, shall be increased proportionately, and
such other adjustment shall be made as may be deemed equitable by the
Administrator. In the event of any other change affecting the Common Stock, such
adjustment shall be made as may be deemed equitable by the Administrator to give
proper effect to such event.

     18.  AMENDMENT OF THE PLAN. The Board may at any time, and from time to
time, amend the Plan in any respect, except that without the approval, within 12
months of such Board action, by the stockholders, no amendment shall be made
increasing the number of shares approved for the Plan or making any other change
that would require stockholder approval in

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order for the Plan, as amended, to qualify as an "employee stock purchase plan"
under Section 423(b) of the Code.

     19.  INSUFFICIENT SHARES. If the total number of shares of Common Stock
that would otherwise be purchased on any Exercise Date plus the number of shares
purchased under previous Offerings under the Plan exceeds the maximum number of
shares issuable under the Plan, the shares then available shall be apportioned
among Participants in proportion to the amount of payroll deductions accumulated
on behalf of each Participant that would otherwise be used to purchase Common
Stock on such Exercise Date.

     20.  TERMINATION OF THE PLAN. The Plan may be terminated at any time by the
Board. Upon termination of the Plan, all amounts in the accounts of Participants
shall be promptly refunded.

     21.  GOVERNMENTAL REGULATIONS. The Company's obligation to sell and deliver
Common Stock under the Plan is subject to obtaining all governmental approvals
required in connection with the authorization, issuance, or sale of such stock.

     The Plan shall be governed by Delaware law except to the extent that such
law is preempted by federal law.

     22.  ISSUANCE OF SHARES. Shares may be issued upon exercise of an Option
from authorized but unissued Common Stock, from shares held in the treasury of
the Company, or from any other proper source.

     23.  TAX WITHHOLDING. Participation in the Plan is subject to any minimum
required tax withholding on income of the Participant in connection with the
Plan. Each employee agrees, by entering the Plan, that the Company and its
Subsidiaries shall have the right to deduct any such taxes from any payment of
any kind otherwise due to the employee, including shares issuable under the
Plan.

     24.  NOTIFICATION UPON SALE OF SHARES. Each employee agrees, by entering
the Plan, to give the Company prompt notice of any disposition of shares
purchased under the Plan where such disposition occurs within two years after
the date of grant of the Option pursuant to which such shares were purchased.

     25.  EFFECTIVE DATE AND APPROVAL OF SHAREHOLDERS. The Plan was adopted by
the Board of Directors on May 12, 2004 and shall take effect on the Effective
Date, subject to approval, in accordance with applicable state law, by the
holders of a majority of the votes cast at a meeting of stockholders at which a
quorum is present or by written consent of the holders of a majority of the
votes represented by all outstanding shares of stock of the Company entitled to
vote thereon.

Approved by the Stockholders on June 18, 2004


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