EXHIBIT 10.2
                                                                    ------------

Branford, Connecticut                    Date of this Agreement: August 10, 2004


                                NEWALLIANCE BANK
                               SECURITY AGREEMENT


1. WHAT SOME OF THE WORDS MEAN.

      "Secured Party" means NewAlliance Bank, 195 Church Street, New Haven,
Connecticut 06510 and what are called its "successors and assigns."

"Debtor" means, individually and collectively, the following persons and/or
entities: CAS MEDICAL SYSTEMS, INC.

      "This Agreement" means this Security Agreement.

"Borrower" means, individually and collectively, the following persons and/or
entities: CAS MEDICAL SYSTEMS, INC.

      "Commercial Loan Agreement" means and includes, individually and
collectively (applicable box is checked):

[X] Commercial Line of Credit Note and Loan Agreement dated the date hereof
from the Borrower to the Secured Party with a credit limit of $3,000,000.00:

[ ] Commercial Term Loan Note dated the date hereof from the Borrower to the
Secured Party with an initial principal balance of $______________.

2. DEBTOR GRANTS A SECURITY INTEREST IN COLLATERAL. For valuable consideration,
the receipt and sufficiency of which is hereby acknowledged by the parties, the
Debtor does hereby grant to the Secured Party a security interest in the
property (the same being hereinafter referred to as "Collateral") described in
Exhibit A attached hereto and made a part hereof, to secure payment of all of
Borrower's indebtedness, obligations and liabilities to Secured Party, whether
arising under this Agreement, the Commercial Loan Agreement, any extension or
modification thereof, any promissory note, any guaranty or endorsement or
otherwise, whether direct or indirect, joint or several, absolute or contingent
(all of which indebtedness, obligations and liabilities are hereinafter
sometimes called the "Obligations").

3. WARRANTIES AND COVENANTS. The Debtor hereby warrants and covenants that the
Collateral is used primarily for business purposes and that the tangible
personal property forming a part of the Collateral shall be kept and maintained
within the State of Connecticut; that Debtor will promptly notify Secured Party
of any change in the State wherein said Collateral is located and will not
remove said Collateral from said State without the prior written consent of the
Secured Party.

      Debtor hereby further warrants and covenants that:

      (a) Debtor is the Owner of the Collateral free from any adverse lien,
security interest or encumbrance, except for the security interest granted
hereby, and Debtor will defend the Collateral against all claims and demands of
all persons at any time claiming the same or any interest therein.

<PAGE>

      (b) No financing statement covering all or any part of the Collateral is
on file in any public office (other than those expressly consented to in writing
by Secured Party), and at the request of Secured Party, Debtor will execute or
join with Secured Party in executing one or more financing statements pursuant
to the Uniform Commercial Code in form satisfactory to Secured Party and will
pay the cost of filing the same or filing or recording this Agreement in all
public offices wherever filing or recording is deemed by Secured Party to be
necessary or desirable. A photocopy of this Agreement may be filed as a
financing statement at the option of the Secured Party. The Debtor hereby
authorizes the Security Party to file one or more financing statements without
the Debtor's signature in any jurisdiction deemed reasonable or necessary by
Secured Party to further perfect the security interests granted hereunder and
Debtor hereby appoints the Secured Party as its attorney-in-fact, which
appointment is coupled with an interest and is irrevocable, to sign Debtor's
name to any such financing statement.

      (c) Debtor will not sell or offer for sale or otherwise transfer all or
any part of the Collateral or any interest therein (except sales in the ordinary
course of the Debtor's business) without the prior written consent of Secured
Party.

      (d) Debtor will have and maintain insurance at all times with respect to
all insurable Collateral against risks of fire (including so-called extended
coverage), theft and such other risks as Secured Party may require, containing
such terms, in such form, for such periods and written by such companies as may
be satisfactory to Secured Party, such insurance to be payable to Secured Party
and Debtor as their interests may appear; all policies of insurance shall
provide for thirty (30) days prior written minimum cancellation notice to
Secured Party; Debtor shall furnish Secured Party with certificates or other
evidence satisfactory to Secured Party of compliance with the foregoing
insurance provisions; and Debtor hereby appoints Secured Party as
attorney-in-fact for Debtor, which appointment is coupled with an interest and
is irrevocable, for the purpose of obtaining, adjusting, settling and canceling
such insurance and endorsing any drafts.

      (e) Debtor will keep the Collateral free from any adverse lien, security
interest or encumbrance (other than those expressly consented to in writing by
Secured Party) and in good order and repair and will not waste or destroy the
Collateral or any part thereof; Debtor will not use the Collateral in violation
of any statute or ordinance; and Secured Party may examine and inspect the
Collateral at any time, wherever located.

      (f) Debtor will pay promptly when due all taxes and assessments upon the
Collateral or for its use or operation or upon this Agreement or upon any
instrument or document creating the Obligations.

      (g) Debtor will permit the Secured Party, or any agent or person
designated by the Secured Party, at any time during normal business hours to
enter the premises of the Debtor for the purpose of inspecting and/or appraising
the Collateral, provided, however, that unless an event of default has occurred
or the Secured Party believes in good faith that there has been an adverse
change in market or other conditions that may affect the value of the
Collateral, the Debtor shall be required to pay the costs of such inspection
and/or appraisal only once every three (3) years.

      (h) At its option, Secured Party may discharge taxes, liens or
security interests or other encumbrances at any time levied or placed on the
Collateral, may pay for insurance on the Collateral, and may pay for the
maintenance and preservation of the Collateral. Debtor agrees to reimburse
Secured Party on demand for any payment made, or any expense incurred by Secured
Party pursuant to the foregoing authorization. Interest shall accrue on any such
expenditure until paid at the highest rate chargeable to the Borrower under any
Obligation. Until an event of default has occurred and Secured Party has given
Debtor notice containing directions regarding the Collateral, Debtor may have
possession of the Collateral and use it in any lawful manner not inconsistent
with this Agreement and not inconsistent with any policy of insurance thereon.

4. DEFAULT. Debtor shall be in default under this Agreement upon the happening
of any of the following events or conditions:

      (a) Default by the Borrower with respect to any of the Obligations,
including but not limited to, a failure to promptly pay or perform (or any other
"Event of Default") under the Commercial Loan Agreement;

<PAGE>

      (b) Default by the Debtor in the performance of or compliance with any
term or covenant applicable to it contained herein or in any other instrument,
document or agreement securing any Obligation;

      (c) Any warranty, representation or statement made or furnished to Secured
Party by or on behalf of Debtor proves to have been false in any material
respect when made or furnished;

      (d) Loss, theft, substantial damage, destruction, sale (except in the
ordinary course of Debtor's business) to or of any of the Collateral, or the
making of any levy, seizure or attachment thereof or thereon or if all or any
part of the Collateral is subjected to a lien, encumbrance or security interest
(other than the security interest granted herein); or

      (e) Dissolution, termination of existence, insolvency, business failure,
appointment of a receiver of any part of the property of, assignment for the
benefit of creditors by, or the commencement of any proceeding under any
bankruptcy or insolvency laws, by or against Debtor or any guarantor or surety
for Borrower.

5. REMEDIES UPON DEFAULT. Upon such default and at any time thereafter, Secured
Party may declare all Obligations secured hereby immediately due and payable and
shall have the remedies of a secured party under the Uniform Commercial Code.
Secured Party may require Debtor to assemble the Collateral and make it
available to Secured Party at a place to be designated by Secured Party which is
reasonably convenient to both parties. Unless the Collateral is perishable or
threatens to decline speedily in value or is of a type customarily sold on a
recognized market, Secured Party will give Debtor reasonable notice of the time
and place of any public sale thereof or of the time after which any private sale
or any other intended disposition thereof is to be made. The requirements of
reasonable notice shall be met if such notice is mailed, postage prepaid, to the
Debtor at its principal place of business, at least seven (7) days before the
time of the sale or disposition. Any proceeds of any disposition of any of the
Collateral shall be applied in the manner and order as provided in the Uniform
Commercial Code. Secured Party's expenses shall include, without limitation,
expenses of retaking, holding, preparing for sale, selling, leasing and the like
and Secured Party's reasonable attorney's fees and legal expenses.

6. GENERAL.

      (a) INFORMATION REGARDING DEBTOR AND COLLATERAL. Debtor understands and
agrees that the condition of and circumstances surrounding the Collateral and
Debtor's financial condition are of material and continuing importance to
Secured Party. Accordingly, Debtor hereby agrees to promptly provide Secured
Party with such information as we may request from time to time (including, if
requested, information pertaining to any Collateral and Debtor's financial
condition). All such information shall be in form, scope and detail acceptable
to Secured Party, and, if Secured Party so requests, will be reviewed, compiled
or audited by persons or firms reasonably acceptable to Secured Party (all at
Debtor's expense).

      (b) GIVING OF NOTICES. Unless the law requires a different method, any
notice that must be given to Debtor under this Agreement will be given by hand
delivery, or by mailing it by first class mail, to the address, as applicable,
stated below. It shall be mailed or delivered to Debtor at a different address
if Debtor gives Secured Party a notice of that different address. Unless the law
or this Agreement provides otherwise, all notices that must be given to the
Secured Party under this Agreement will be given by mailing it by postage
prepaid registered first class mail (return receipt requested) to the Secured
Party at the address stated above in Section 1 (directed to the attention of the
Commercial Loan Administration Department) or to a different address if Secured
Party gives Debtor notice of that different address.

      (c) CONNECTICUT LAW. This Agreement is being made in the State of
Connecticut and will be governed by the laws of the State of Connecticut.

      (d) SEVERABILITY. If any part of this Agreement is found to be invalid,
illegal or unenforceable by a court, the other parts of this Agreement will stay
valid and enforceable and will be read as if the invalid or unenforceable part
had not been included.

<PAGE>

      (e) CAPTIONS. The headings of the various sections, subsections and
paragraphs of this Agreement are included for convenient reference only, and
shall not be included in the interpretation of this Agreement.

      (f) BINDING EFFECT. This Agreement shall be binding upon Debtor and
Debtor's successors and assigns (or, if applicable, executors and heirs). This
Subsection 6(f) shall not, however, be construed as permitting Debtor to assign
Debtor's rights and/or responsibilities under this Agreement. Debtor understands
and agrees that such an assignment is prohibited. Secured Party is permitted to
assign its rights and benefits under this Agreement with or without advance
notice to Debtor.

      (g) MODIFICATIONS. This Agreement may be amended only by a written
agreement signed by Debtor and Secured Party.

      (h) NO WAIVER. Neither failure or delay on Secured Party's part to
exercise any right, power or privilege under this Agreement shall operate as a
waiver thereof, nor shall any single or partial exercise of any right, power, or
privilege under this Agreement preclude any other or further exercise thereof or
the exercise of any other right, power or privilege.

      (i) WAIVER OF NOTICE, HEARING AND BOND FOR PREJUDGMENT REMEDY. Debtor
hereby acknowledges that the transaction of which this agreement is a part is a
commercial transaction, and to the extent allowed under chapter 903a of the
Connecticut General Statutes or by other applicable law, hereby waives (a) all
rights to notice and prior court hearing or court order in connection with any
and all prejudgment remedies to which any holder of this agreement may become
entitled by virtue of any default under a provision of this agreement or under
any other agreement related to this agreement and (b) all rights to request that
the holder of this agreement post a bond, with or without surety, to protect
debtor or any other person or entity liable under this agreement against damages
that may be caused by any prejudgment remedy sought or obtained by the holder of
this agreement by virtue of any default under the provisions of this agreement
or under any security agreement related to this agreement, and debtor hereby
consents to the issuance of any such prejudgment remedy without such a bond.

      (j) WAIVER OF JURY TRIAL. Debtor hereby knowingly, voluntarily,
intentionally and irrevocably, waives any and all right to a trial by jury in
any action or proceeding to enforce or defend or clarify and right, power,
remedy, or defense arising out of or related to this agreement, or the
transactions contemplated herein, whether sounding in tort or contract or
otherwise, or with respect to any course of conduct, course of dealing,
statements (whether verbal or written) or actions of any party; and debtor
further agrees that any such action or proceeding shall be tired before a judge
and not before a jury. Debtor further waives any right to seek to consolidate
any such litigation in which a jury trial cannot or has not been waived.
Further, debtor hereby certifies that no representative or agent of the secure
party, nor the secured party's counsel, has represented, expressly or otherwise,
that the secured party would not, in the event of such litigation, seek to
enforce this waiver provision. Debtor acknowledges that the provisions of this
paragraph are a material inducement to the secured party's decision to enter
into the transactions contemplated by this agreement.

SERVICE OF PROCESS. Debtor hereby consents to the jurisdiction of any state or
federal court located within the state of Connecticut and waive personal service
of any and all process upon debtor, and consents that all such service or
process be made by registered mail directed to the applicable address stated
below and service so made shall be deemed to be completed upon actual receipt
thereof.

SIGNATURE OF DEBTOR. By signing below, you agree, as a debtor, to the terms and
conditions of this agreement as of the date of this agreement shown above.

<PAGE>

DEBTOR: CAS MEDICAL SYSTEMS, INC.

/s/ Louis Scheps
-------------------------
By:  Louis Scheps
Its:  President & CEO


44 East Industrial Road
Branford, CT  06405