REVOLVING CREDIT PROMISSORY NOTE

Exhibit 4.1

REVOLVING CREDIT PROMISSORY NOTE

     FOR VALUE RECEIVED, CDSI Holdings Inc., a Delaware corporation (the “Borrower”) hereby unconditionally promises to pay to the order of Vector Group Ltd., having an office at 100 S.E. Second Street, 32nd Floor, Miami, Florida 33131 (the “Lender”), on December 31, 2012, or such later date as requested by Borrower and agreed to in writing by the Lender in its sole discretion (the “Maturity Date”), the principal sum of Fifty Thousand Dollars ($50,000.00) (the “Commitment Amount”) or such lesser amount as may be outstanding under this Revolving Credit Promissory Note (the “Note”), together with accrued unpaid interest as set forth herein.

1. Revolving Facility .

     1.1 Subject to the terms hereof, the Lender may, in its sole discretion, agree to make advances (each an “Advance”) to the Borrower upon the Borrower’s request in an aggregate amount not to exceed Fifty Thousand dollars ($50,000.00) or such lesser amounts that when combined, shall not exceed the Commitment Amount. The Borrower acknowledges and agrees that the Lender has no obligation of any kind to make any Advance and may elect at any time and without cause to not make any Advances. The Borrower and the Lender shall agree upon mutually acceptable borrowing notice procedures.

     1.2 The Lender’s records of all Advances and payments made hereunder shall, absent manifest error, be binding on the Borrower for all purposes.

     1.3 Principal amounts repaid or prepaid hereunder, subject to the terms hereof, may be reborrowed.

2. Interest; Net Payments .

     2.1 All loans outstanding hereunder shall bear interest, upon any net balance outstanding at the close of each day, which interest will be payable by the Borrower in arrears, on the Maturity Date, until the principal is paid in full pursuant to the terms hereof, at a rate of interest (calculated on a year of 360 days) equal to eleven percent (11%) per annum; provided , however , that if the Borrower does not pay the outstanding principal and interest due and owing by the Maturity Date, such amount(s) shall automatically be compounded at the Default Rate (defined below). Principal shall be repaid in full on the Maturity Date or upon such earlier date upon which demand therefor is made by the Lender; provided however , that two (2) days advance notice of any such demand is given to the Borrower.

     2.2 Any amounts outstanding on the earliest of (i) the occurrence of an Event of Default and the passage of any applicable cure period or (ii) the Maturity Date, to the extent permitted by applicable law, shall accrue interest at sixteen percent (16%) per annum (calculated on a year of 360 days) compounded quarterly (the “Default Rate”).

     2.3 All payments hereunder shall be made to the account specified by the Lender to the Borrower in immediately available funds in United States Dollars without setoff, defense or counterclaim or withholding on account of taxes, levies, duties or any other deduction whatsoever. Whenever any payment to be made hereunder shall be otherwise due on a day which is not a business day, such payment shall be made on the next succeeding business day, unless such date falls into the next calendar month (in which case payment is to be made on the preceding date) and such extension of time shall in such case be included in the computation of interest.

3. Representations and Warranties; Covenants .

     3.1 As an inducement for the Lender to make Advances hereunder, the Borrower hereby represents, warrants and covenants that on the closing date and at the time of each Advance that:

          (a) it is a Delaware corporation duly organized, validly existing and in good standing;

          (b) it has the authority and has taken all necessary action in order to execute and deliver this Note and to perform the terms and provisions set forth herein;

          (c) the Borrower’s obligations under this Note are legal, valid and binding and enforceable against the Borrower in accordance with their terms, except as such enforceability may be limited by bankruptcy, insolvency or similar laws affecting the enforcement of creditor’s rights in general;

          (d) the Borrower shall provide the Lender with such financial information regarding the Borrower, its affiliates and their respective business operations as the Lender may from time to time request;

          (e) without the prior consent of the Lender, the Borrower shall not amend its governing documents in any manner that would be adverse to the Lender;

          (f) without the prior consent of the Lender, the Borrower shall not directly or indirectly incur any indebtedness for borrowed money (or similar liability); and

          (g) without the prior consent of the Lender, the Borrower shall not directly or indirectly encumber, pledge, hypothecate or charge, any of its assets or properties or sell all or substantially all of its assets or properties.

4. Intentionally Omitted.

5.  Events of Default .

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