EXHIBIT 4.3
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                            CAS MEDICAL SYSTEMS, INC.
                          EMPLOYEE STOCK PURCHASE PLAN

            1. INTRODUCTION

            The CAS Medical Systems, Inc. Employee Stock Purchase Plan (the
"Plan") is designed to provide Eligible Employees with the opportunity to own
common stock ("Common Stock") in CAS Medical Systems, Inc. (the "Company")
through a payroll-deduction based employee stock purchase plan, thereby
stimulating Eligible Employees' interest in the growth and prosperity of the
Company.

            The Plan is intended to be a qualified employee stock purchase plan
under Section 423 of the Internal Revenue Code of 1986, as amended (the "Code"),
or any successor provision thereto, and the Plan shall be construed in
accordance with such purpose.


            2. ELIGIBLE EMPLOYEES

            An "Eligible Employee" is any person (i) who is an employee of the
Company or a U.S. subsidiary of the Company designated as a "participating
subsidiary" (each such entity being referred to as a "Participating Employer")
by the Company's Compensation Committee (the "Committee") and (ii) who is
customarily employed for at least twenty (20) hours a week as of the Initial
Payroll Deduction Date (as defined below). An Eligible Employee shall be
eligible to purchase Common Stock under this Plan in accordance with the terms
of the Plan.

            Any provision of this Plan to the contrary notwithstanding, no
otherwise Eligible Employee shall be granted a Purchase Right under this Plan:

                  (a) if, immediately after the grant such Eligible Employee
would own shares and/or hold outstanding Purchase Rights to purchase 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 subsidiary of the Company; or

                  (b) that permits the Eligible Employee to purchase more than
$25,000 worth of Common Stock (or such greater amount as may be then permitted
by Section 423, or any successor provision, of the Code), based on the Fair
Market Value of the Shares determined at the time such Purchase Right is
granted, for each calendar year in which such Purchase Rights are outstanding
under all employee stock purchase plans of the Company and its subsidiaries; or

                  (c) that permits the Eligible Employee to purchase more than
1,500 shares during any Offering Period.

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            An Eligible Employee who elects to participate as provided in
Paragraph 4 shall be a referred to as a "Participant".


            3. OFFERING

            While the Plan is in effect, two Offering Periods shall commence in
each calendar year, unless otherwise determined by the Committee. The Offering
Periods shall consist of the six-month periods commencing on each January 1 and
July 1, except that the first offering period shall, unless otherwise determined
by the Committee, commence on July 1, 2004 and extend through December 31, 2004.
The first day of the Offering Period shall be known as the "Offering Date".

            For each Offering Period, the last business day of the term of the
Offering Period shall be the date of exercise (the "Purchase Date") unless the
Committee determines otherwise. For each Offering, the purchase price per share
of stock (the "Purchase Price" or "Exercise Price") will be the lower of the
average of the high and low price of the Common Stock on the OTC Bulletin Board
(the "Average Price") on (i) the Offering Date or (ii) the Purchase Date, less
fifteen percent (15%) (the "Discount"). Notwithstanding the foregoing, the
Committee may determine in its discretion and in advance of the commencement of
the Offering Period that a smaller Discount shall apply. In no event shall the
Committee determine a Purchase Price that is less than the lowest price that
employee stock purchase plans are permitted to establish under Section 423 (or
any successor provision) of the Code nor shall a Purchase Right granted under
this Plan be exercisable for a period of time longer than that permitted under
Section 423 (or any successor provision) of the Code.

            The Committee shall in its discretion determine the terms and
conditions under which each Offering shall be made and shall authorize and
determine in advance of the Offering the aggregate number of shares of Common
Stock that may be issued pursuant to each Offering. The Committee shall
determine the exact number of shares of Common Stock utilized in each Offering
and shall report such information to the Treasurer or his or her delegate. The
terms of such Offering shall comply in all respects with Section 423 of the
Code, including the Purchase Price and the duration of the exercise period for
such Offering.

            Notice of each Offering will be given to Eligible Employees with
full details as to the aggregate number of shares offered, the Purchase Price
per share for the Offering, the restrictions on the maximum number of shares
purchasable by the Participant with respect to each Offering Period, the amount
of payroll deductions to be made, and any pro rata reduction required in
accordance with Paragraph 5.

            Under the terms of this Plan, all Eligible Employees granted a
Purchase Right pursuant to an Offering shall have the same rights and privileges
with respect to such Purchase Right, except that the number of shares of Common
Stock that may be purchased by any Eligible Employee will be based on his or her
total Payroll Deductions during the Offering Period.

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            4. PAYROLL DEDUCTIONS; PURCHASE OF COMMON STOCK

            An Eligible Employee may become a Participant in the Plan by filing
on or before the Offering Date of an Offering a completed Stock Purchase form
provided by the Company (i) authorizing Payroll Deductions (as described herein)
and (ii) subscribing to purchase that number of shares of Common Stock
purchasable based on the total Payroll Deductions deducted with respect to the
Offering Period and the Purchase Price determined in accordance with Paragraph
3. Any such Stock Purchase form pursuant to this Paragraph 4 shall remain in
effect for subsequent Offerings unless such Participant completes and files a
new Stock Purchase form and Payroll Deduction authorization, which shall be
applied only to future Offerings. A Participant may cancel his participation in
any Offering in accordance with Paragraph 8.

            (a) Eligible Employees may elect to authorize their Participating
Employer to make Payroll Deductions from Compensation in terms of either whole
percentage amounts or whole dollar amounts (subject to any minimum percentage or
dollar amount per payroll period that the Committee shall establish); provided,
however, that no Payroll Deduction for any Offering Period shall exceed ten
percent (10%) percent of a Participant's Compensation during the period that
begins on the Offering Date and ends on the Purchase Date.

            "Compensation" shall mean a Participant's base salary earnings for
the Offering Period, except that, with respect to Participants paid partially or
entirely on commission, "Compensation" shall mean such Participant's Average
Benefit Base Rate of compensation for the Offering Period. "Average Benefit Base
Rate" shall equal an amount, determined by taking the prior year's year regular
earnings from January 1 through August 31 of such year, plus commissions for the
same period, divided by 8 and multiplied by the number of months in the Offering
Period.

            (b) Unless the Committee shall specify otherwise, deductions shall
begin in the first pay period commencing after the Offering Date (the "Initial
Payroll Deduction Date"). All Payroll Deductions may be used by the Company for
general corporate purposes. A separate bookkeeping account ("Book Account")
shall be maintained by the Company for each Participant, and the amount of each
Participant's Payroll Deductions shall be credited to such account. Except as
provided in Paragraph 9, no interest shall be paid on the balance of the
Employee's Book Account. Payroll Deductions shall not be held in any segregated
account or trust fund and may be commingled with the general assets of the
Company and used for general corporate purposes.

            (c) Unless the Committee shall specify otherwise, each Participant
will be granted an allotment for the number of shares of Common Stock which are
purchasable, computed as the aggregate Payroll Deduction designated by such
Participant on such Participant's Stock Purchase form to be deducted during the
term of the Offering divided by the Purchase Price (determined in accordance
with Paragraph 3), subject to the provisions of Paragraph 5 below. If such
amount does not result in a whole number of shares of Common Stock, the number
of shares will be decreased to the next lowest whole number.

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            (d) Unless an Employee exercises his right to cancel and makes a
request of the Committee prior to the Purchase Date to withdraw his Book Account
in cash, the amount of an Employee's Book Account shall automatically be used to
exercise his Purchase Right on the Purchase Date. The Employee's Purchase Right
will be exercised, in purchases of whole shares of Common Stock, to the extent
of the amount in the Employee's Book Account; provided, however, the Employee is
not limited in the exercise of his Purchase Right to the amount credited to his
Book Account. The Employee may supplement the amount of his Book Account to
exercise his Purchase Right (for the number of shares of Common Stock that the
Employee had elected to purchase during the Offering Period pursuant to
Paragraph 4) by paying cash and/or tendering Shares (if permitted) to the Plan
Administrator.

            (e) Any Payroll Deductions not applied to the purchase of Shares on
the Purchase Date (because not sufficient to purchase whole Shares) shall remain
in the Participant's Book Account for the purchase of shares of Common Stock
under the next Offering, unless such Participant withdraws from such next
Offering, or is not eligible to participate in such Offering (including because
of his premature disposition of Shares acquired under the Plan under
subparagraph (f) below), in which case such amount shall be distributed in cash
to the Participant after the Purchase Date without interest. Any Payroll
Deductions not applied to the purchase of shares of Common Stock by reason of
the limitation on the maximum number of Shares purchasable by an Employee on the
Purchase Date shall be promptly returned in cash to the Employee without
interest.

            (f) If a Participant Disposes of Shares acquired under this Plan
prior to having held such Shares for a twelve (12) month period from the
Purchase Date, then the Participant shall be ineligible to purchase additional
shares under any Offering in effect as of the date of disposition, any Payroll
Deductions taken with respect to the Offering Period for such Offering shall be
returned in accordance subparagraph (e), and the Participant shall further be
ineligible to participate in the purchase of Shares during the next succeeding
Offering Period.


            5. OVERSUBSCRIPTIONS

            In the event the number of shares for which subscriptions are
received exceeds the number of shares offered as determined under Paragraph 3,
the number of shares allotted to each Participant will be proportionately
reduced.


            6. RIGHTS AS A STOCKHOLDER

            A Participant will have none of the rights or privileges of a
stockholder of the Company until the full purchase price of such Participant's
shares has been paid and such shares of Common Stock have been issued to the
Participant and recorded in the books of the Company (or its transfer agent).

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            7. ISSUANCE OF STOCK

            Unless a Participant cancels such Participant's Purchase Right as
provided below, it will be exercised and become an obligation to take the shares
of Common Stock as of the Purchase Date. Within a reasonable time after the
Purchase Date, the number of shares purchased by a Participant, determined as
provided in Paragraph 4, will be credited to such Participant.

            The shares will be issued in the name of the employee or, upon such
employee's request, jointly in such employee's name and that of a family member
as specified on such employee's Stock Purchase Registration form.

            The Committee, in its discretion, may impose restrictions on the
transferability of shares of Common Stock acquired pursuant to this Plan, and
may cause to be placed on all stock certificates, other evidences of ownership,
legends or other indicators setting forth any such restrictions on
transferability instructing the transfer agent to notify the Company of any
transfer of such shares, and may require that any shares acquired pursuant to
the Plan be held in the Participants' Book Accounts until the expiration of any
restrictions. Such restrictions, if any, shall apply uniformly to all
Participants with respect to any Offering.


            8. RIGHT TO CANCEL

            Prior to the final Payroll Deduction to be made pursuant to any
Offering, a Participant may cancel all or any part of such Participant's right
to purchase by filing a notice of cancellation with the Company. Promptly after
the Company's receipt of such notice, the Participant will receive the Payroll
Deductions then credited to his Book Account, without interest thereon. Rights
to purchase which have been canceled pursuant to this Paragraph may not be
reinstated at a later date. However, the Participant may participate with
respect to future Offerings, provided he remains an Eligible Employee.


            9. TERMINATION OF EMPLOYMENT

            If a Participant (i) dies, (ii) retires on or after reaching age 55
with 10 years of service, or (iii) terminates due to disability (as defined in
the Company's long-term disability plan) prior to such Participant's final
Payroll Deduction for an Offering, such Participant or such Participant's legal
representative may, within a period of three (3) months following the
Participant's death or retirement either:

                  (a) cancel such Participant's Purchase Right and request
payment in cash of the entire amount which has been deducted under the Plan plus
interest as computed below, or

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                  (b) receive the number of full shares of Common Stock which
the Payroll Deductions will purchase, at the Purchase Price, and receive the
balance, if any, in cash.

            Notice of choice between (a) and (b) above shall be given to the
Company in writing and if such notice is not received within the prescribed
period, the Company shall act in accordance with (a) above.

            If a Participant's employment is otherwise terminated, such
Participant's only right will be to receive in cash the amount which has been
deducted under the Plan, together with interest, calculated at the average
passbook rate (or such other rate as the Committee shall determine), on the
average balance of Payroll Deductions credited to such Participant's Book
Account during the during the Offering Period up to the Participant's
termination date.

            A Participant who remains an employee, but whose name is temporarily
taken off the payroll because of leave of absence, temporary disability,
temporary layoff, military service or for service with another organization to
the mutual benefit of the Company and the employee, may cancel such
Participant's right to purchase and receive the amounts accumulated to such
Participant's credit, or make special arrangements to continue payments, or to
suspend them. In the event that the Participant's Payroll Deductions are
suspended pursuant to this paragraph, but the Participant nevertheless wishes to
exercise his Purchase Right in full, then payment of the Purchase Price must be
made not later than the Purchase Date.


            10. DESIGNATION OF BENEFICIARY.

            (a) A Participant may file a written designation of a beneficiary
who is to receive any shares of Common Stock and/or cash, if any from the
Participant's Book Account under the Plan in the event of such Participant's
death subsequent to the end of an Offering but prior to delivery to the
Participant of such shares of Common Stock or cash. In addition, a Participant
may file a written designation of a beneficiary who is to receive any cash from
the Participant's Book Account under the Plan in the event of such Participant's
death during an Offering.

(b) The Participant may change such beneficiary designation at any time by
written notice to the Committee. In the event of the death of the Participant
and in the absence of a validly designated, surviving, beneficiary under the
Plan, the Company shall deliver such shares of Common Stock and/or cash to the
executor or administrator of the estate of the Participant, or if none has been
appointed, then to the surviving spouse of the Participant or, if none, to such
other person as the Company may designate.


            11. RIGHTS NOT TRANSFERABLE

            No right under this Plan, other than stock issued pursuant to the
terms of the Plan not otherwise subject to restrictions on transfer ("Released
Stock"), shall be assignable, alienable, saleable, or transferable by a

<PAGE>

Participant other than by will or by the laws of descent and distribution. Each
right under this Plan shall be exercisable during the Participant's lifetime
only by the Participant, or, if permissible under applicable law, by the
Participant's guardian or legal representative. No right hereunder (other than
Released Stock) may be pledged, alienated, attached, or otherwise encumbered and
any purported pledge, alienation, attachment, or encumbrance thereof shall be
void and unenforceable against the Company or any affiliate.


            12. ADMINISTRATION

            The Plan shall be administered by the Compensation Committee (the
"Committee") designated by the Board of Directors of the Company to administer
the Plan, which committee shall be composed of persons then serving as Directors
of the Company. The Committee shall have full authority to:

            (i) determine when and how Purchase Rights shall be granted and the
provisions of each Offering of such Purchase Rights;

            (ii) designate from time to time which subsidiaries of the Company
shall be eligible to participate in the Plan;

            (iii) construe and interpret the Plan and Purchase Rights granted
under the Plan;

            (iv) establish rules for the administration of the Plan and make
administrative decisions regarding the Plan; and

            (v) remedy any defect, or omission or inconsistency in the Plan in a
manner and to the extent necessary or expedient to make the Plan fully
effective.

            All designations, determinations, interpretations, and other
decisions made by the Committee under or with respect to the Plan shall be
final, conclusive, and binding upon all persons, including the Company, any
affiliate, any Participant, any holder or beneficiary of any right of
participation, and any employee of the Company or of any affiliate.

            The Committee may delegate any one or more of its administrative
functions (other than those set forth in (i) and (ii) above) to any
individual(s) of its choice, in which case the use of the term "Committee" when
used in reference to such functions under the Plan shall refer to such
delegatee.


            13. ADJUSTMENT UPON CHANGES IN SECURITIES; CORPORATE TRANSACTIONS.

            (a) In the event a stock dividend, extraordinary cash dividend,
spin-off, split-up, combination, exchange of shares, merger, consolidation,
reorganization, recapitalization, or other similar corporate event affects the
Common Stock such that an adjustment is required in order to preserve the

<PAGE>

benefits or potential benefits intended to be made available under the Plan,
then the Committee shall, in its sole discretion, and in such manner as the
Committee may deem equitable, adjust the maximum number of shares available
under the Plan, the number and kind of shares subject to outstanding rights to
purchase, and the terms relating to the purchase price with respect to such
outstanding rights and take such other actions as the Committee, in its opinion,
deems appropriate under the circumstances.

            (b) In the event of a Corporate Transaction, then (i) any surviving
or acquiring entity may continue or assume the Purchase Rights outstanding under
the Plan or may substitute similar rights (including a right to acquire the same
consideration paid to stockholders in the Corporate Transaction) for those
outstanding under the Plan, or (ii) if any surviving or acquiring entity does
not assume such Purchase Rights or substitute similar rights for Purchase Rights
outstanding under the Plan, then the Participants' accumulated Payroll
Deductions shall be used to purchase shares of Common Stock immediately prior to
the Corporate Transaction under the then ongoing Offering, and the Participants'
Purchase Rights under the ongoing Offering shall terminate immediately after
such purchase.


            14. AMENDMENT OR TERMINATION

            The Board of Directors of the Company may, from time to time amend,
suspend or discontinue this Plan for the purpose of meeting any changes in legal
requirements or for any other purpose permitted by law; provided however that
shareholder approval will be required for any amendment that (i) increases the
number of shares of Common Stock that can be issued under the Plan (except for
any adjustment authorized in Paragraph 12(a), or (ii) changes the corporations
whose employees may be offered Purchase Rights under the Plan (except for
changes authorized in Paragraph 2(i). The Committee may also amend or alter the
Plan from time to time in a manner not inconsistent with the Board's power to
amend, suspend or discontinue the Plan.


            15. SHARES OF COMMON STOCK SUBJECT TO THE PLAN; SHAREHOLDER APPROVAL

            (a) The number of shares of Common Stock that may be purchased
through the exercise of Purchase Rights under the Plan shall not exceed one
hundred fifty-thousand (150,000) shares. The shares subject to purchase under
the Plan may consist, in whole or in part, of authorized but unissued shares,
not reserved for any other purpose, or shares acquired by the Plan Administrator
in the market. If any Purchase Right or portion thereof terminates for any
reason without being exercised, then the shares not purchased under such
Purchase Right shall again become available for issuance under the Plan.

            (b) The Plan will be submitted for the approval of the Company's
shareholders within twelve (12) months before or after the Effective Date. No
Purchase Rights may be exercised prior to such shareholder approval. If Company
shareholders do not grant such approval, this Plan shall be rendered void and
without effect and any Payroll Deductions collected from Participants shall be
refunded.

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            16. DEFINITIONS

            Whenever used herein, the following terms shall have the respective
meanings set forth below:

"Board" means the Board of Directors of the Company. Any power reserved to the
Board hereunder may be exercised by the Committee or by any other duly
authorized committee of the Board that the Board may designate from time to
time.

"Committee" means the Executive Compensation and Development Committee, or a
successor committee, appointed by the Board in accordance with Paragraph 12.

"Company" means CAS Medical Systems, Inc. and any successor thereto.

"Corporate Transaction" means the occurrence, in a singe transaction or in a
series of related transactions of any one or more of the following events:

            (i) a sale, lease, license or other disposition of all or
substantially all of the assets of the Company;

            (ii) a sale or other disposition of more than 50% of the outstanding
securities of the Company;

            (iii) a merger, consolidation or similar transaction following which
the Company is the surviving corporation, but the shares of Common Stock
outstanding immediately preceding such transaction are converted or exchanged by
virtue of the merger, consolidation or similar transaction into other property,
whether in the form of cash, securities, or otherwise; or

            (iv) a merger, consolidation or similar transaction following which
the Company is not the surviving corporation.

"Disposes" means, for purposes of Paragraph 4(f), any sale or disposition of
Shares or the withdrawal of Shares from the Book Account maintained for a
Participant by the Plan Administrator.

"Effective Date" means July 1, 2004.

"Fair Market Value" means, on any date, the average of the high and the low
price of a share of Common Stock as reported on the OTC Bulletin Board, or any
other established stock exchange on which the Common Stock is traded.

"Offering" means the grant to Eligible Employees of Purchase Rights to purchase
shares of Common Stock under the Plan.

<PAGE>

"Offering Date" means the date selected by the Committee for an Offering to
commence, which unless otherwise specified by the Committee shall be January 1
and July 1 of each year. The Offering Date shall be the date on which the
Purchase Right is granted in accordance with Treasury Regulation Section
1.421-7(c)(1).

"Plan Administrator" means the Committee, unless the Committee has delegated the
particular administrative function to another person in accordance with
Paragraph 12, in which case "Plan Administrator" shall refer to that person as
regards that particular function.

"Purchase Date" means the date on which Purchase Rights granted under the Plan
shall be exercised and as of which purchases of shares of Common Stock shall be
carried out in accordance with such Offering.

"Purchase Right" means a right to purchase shares of Common Stock granted
pursuant to the Plan.


Dated as of February 19, 2004