EXHIBIT 4.12

                                       RDC
                                  INTERNATIONAL

                           CONVERTIBLE PROMISSORY NOTE

$ 50,000.00                                                        July 16, 2001

FOR VALUE RECEIVED, RDC INTERNATIONAL,  A Florida Corporation,  whose address is
1819 Main Street, Suite 702, Sarasota,  Florida 34236, ("Maker") promises to pay
to Robert and Nancy  Zivitz,  Joint  Tenants  ("Lender"),  whose address is 2053
Harbour Links Drive,  Longboat Key,  Florida 34228, or his (her)  assignee,  the
principal sum of Fifty Thousand Dollars ($50,000.00),  together with interest as
follows:

     o    Simple interest shall accrue on the unpaid principle balance at a rate
          of Ten Percent (10%) per annum and payable at maturity.

In consideration, the Maker agrees to provide the Lender with the following:

     1.   A Stock Purchase  Warrant to purchase 17,000 shares of Common Stock of
          RDC  International,  Inc.  at a price of  Twenty-five  Cents per share
          ($0.25).  The Purchase Warrant is exercisable on the date hereof,  and
          shall expire December 31, 2003.

     2.   A  right  to  convert  all or part of the  principle  and/or  interest
          accrued and payable under this Promissory  Note, into the Common Stock
          of RDC  International,  Inc.  at a price  of  Fifty  Cents  per  share
          ($0.50).

Upon maturity date of the  Promissory  Note,  September 30, 2001,  the Lender(s)
shall have, at his/her sole discretion, the following rights:

     o    Request the immediate payment of principle and accrued interest.

     o    Convert the Promissory Note and accrued  interest into Common Stock of
          RDC International, Inc. at a price of Fifty Cents per share ($0.50).

     o    Convert a fixed amount of the  Principle  and accrued  interest due to
          Lender from the proceeds of the Promissory  Note, into Common Stock of
          RDC  International,  Inc. at a price of Fifty Cents per share ($0.50),
          the balance to be paid in cash.

If default be made in the payment of any provision  under this Note, and if such
default is not made good within  three (3) days,  the entire  principle  sum and
accrued  interest  shall at once  become due and payable  without  notice at the
option of the holder of this Note.  While in default,  the interest rate on this
Note shall be  increased to the highest rate allowed by law, or if no maximum is
prescribed by law, to eighteen percent (18%) per annum. Failure to exercise this
option  shall not  constitute  a waiver of the right to  exercise  the same at a
later date for the same default or for any subsequent  default.  In the event of
defaults in the payment of this Note,  and if the same is placed in the hands of
an attorney at law for  collection,  the  undersigned  hereby  agrees to pay all
costs of  collection  including a  reasonable  attorney's  fee in  original  and
appellate jurisdiction. Presentment, protest and notice are hereby waived.

IN WITNESS  WHEREOF,  the  undersigned  has caused this Note to be signed by its
duly authorized  Officer,  and this Note to be dated ths _16th_ day of _ July_ ,
2001.

                                 RDC INTERNATIONAL, INC.


                                 By: /s/ John Harkola
                                 --------------------------------------
                                 John Harkola, Chief Executive Officer