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                                                                    Exhibit 10.4

                         NATIONAL SCIENTIFIC CORPORATION
                      MASTER PURCHASE & LICENSING CONTRACT
                            Contract Number NSC-UR103

This Contract is dated this 12th day of January, 2001

By and Between

<TABLE>
<S>                                   <C>
Name:      OZAKI KOREA CO., LTD.      Name:    National Scientific Corporation
           (a Korean Company)                  (a Texas State U.S. corporation)

Address:   #1208 [ILLEGIBLE]          d/b/a     NSC
           [ILLEGIBLE]  , Seoul                 4455 E. Camelback E-160
           Korea                                Phoenix, AZ 85018 USA

Telephone: 82-2-3273-6834             Telephone: 602-954-1492
Fax:       82-2-3273-6804             Fax:       602-954-1499
           ("Vendor")                            ("NSC")
</TABLE>

1.    Description and Term. This Contract establishes the basic terms and
      conditions which shall govern all Orders for Equipment, Software or
      Services between the parties and shall be incorporated by reference in
      Orders. These terms and conditions can only be varied in writing signed by
      both parties. Unless otherwise agreed to in writing by Vendor and NSC, if
      any printed term or condition contained in any Purchase Order,
      acknowledgement or other form used by Vendor is inconsistent with any term
      or condition contained herein, the provisions of this contract shall apply
      and take precedence. This Contract shall remain in effect for a term of 2
      years unless terminated by either party upon ninety (90) days prior
      written notice or otherwise under of the attached Terms and Conditions.

2.    Orders. Orders for Equipment, Software, or Services must be in writing and
      shall specify a Purchase Order number, the above Contract Number, the
      requested delivery date, the Equipment, Software or Services to be
      Purchased or licensed, the quantities, the prices, and the desired
      delivery location. No Order will be binding until issued in writing by NSC
      and accepted by Vendor in writing.

3.    Prices / Terms and Conditions. All Purchases and sales are subject to the
      attached Terms and Conditions.

The undersigned Vendor has read and understands this Contract (including the
Terms and Conditions) and is not entering into this Contract on the basis of any
representations not expressly set forth in this Contract.

<TABLE>
<CAPTION>
            Vendor                                 NSC
<S>                                     <C>
By:    OZAKI KOREA CO. LTD.             By:    /s/ Michael A. Grollman
Name:  [ILLEGIBLE]                      Name:  Michael A. Grollman
Title: President                        Title: C.O.O., Executive V.P.
Date:  1-12-2001                        Date:  1-12-2001
</TABLE>

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             NSC MASTER PURCHASE & LICENSING CONTRACT, PAGE 1 OF 3
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l.    PRICES; TAXES, PAYMENT.

      1.1   PRICES. Prices and quantities for Equipment and Software, and
            Services will be specified in each Purchase Order. Unless otherwise
            specified in the Purchase Order, all currency amounts and payments
            will be in U.S. dollars.

      1.2   TAXES. Tax terms for Equipment and Software, and any Services will
            be specified in each Purchase Order. In the event that such terms
            are not specified, then the Vendor shall report and pay all excise,
            value added, use and other domestic and foreign taxes (excluding
            only those taxes based on net income) designated, levied, or based
            (i) upon the Purchase price or any other amounts payable under this
            Contract; (ii) on account of this Contract; or (iii) with respect to
            the Equipment, Software or the Services. Vendor shall indemnify and
            hold harmless NSC from all claims and liability resulting from
            Vendor's failure to report or pay such amounts.

      1.3   SHIPMENT. Shipment and delivery terms for Equipment and Software
            will be specified in each Purchase Order. In the event that such
            terms are not specified, then the Vendor shall be responsible for
            all shipment costs FOB the NSC warehouse is Los Angeles, California,
            USA.

      1.4   TITLE. Title to the Equipment and Software shall pass to NSC upon
            NSC's receipt of the Equipment.

      1.5   PAYMENT. NSC shall pay all amounts due to Vendor according to the
            terms specified in each Purchase Order. In the event that the
            Purchase Order does not specify payment terms, the default terms
            shall be in U.S. dollars Net 90 days of accepted delivery by NSC.

2.    WARRANTIES, REPRESENTATIONS AND COVENANTS OF VENDOR. In addition to any
      other Contracts of Vendor set forth in this Contract, Vendor makes the
      following warranties, representations and covenants:

      2.1   RISK OF LOSS. Until receipt by NSC in its designated warehouse,
            Vendor shall bear liability for all risk of loss or damage to any
            Equipment.

      2.2   WARRANTY SUPPORT AND RETURNS. Vendor will provide warranty support
            to its users, if Vendor offers such support. NSC will have no
            obligation to pay Vendor for defective units, and will have the
            right to return such to Vendor or to request a credit from the
            Vendor for such units. Vendor is responsible for management of
            defective returns.

      2.3   COMPLIANCE WITH LAWS. Vendor will comply with all foreign, federal,
            state and local laws relating to the Purchase, use and operation of
            the Equipment and Software, including without limitation all
            applicable export laws. Vendor agrees that it will not export or
            re-export the Equipment or Software without the appropriate United
            States and foreign government licenses and will not export or
            re-export the Equipment or Software to any countries where export or
            re-export is prohibited by applicable government law or regulations.
            Vendor shall have full responsibility for compliance with all laws
            that require registration or approval of this Contract or any
            governmental approval for sale or use of the Equipment or Software
            in any jurisdiction where Vendor Purchases or uses the Equipment or
            Software, and shall bear all costs associated with such compliance.
            Vendor shall indemnify and hold harmless NSC for any damages that
            result from a breach of this Section, and such indemnity shall
            survive expiration or termination of this Contract.

3.    WARRANTIES AND REPRESENTATIONS OF NSC. In addition to any other Contract
      of Vendor set forth in this Contract, NSC makes the following warranties,
      representations and covenants:

      3.1   INSURANCE. NSC shall maintain, at its own expense and with
            established insurance companies, adequate workers' compensation,
            comprehensive general liability and automobile liability insurance
            coverage and shall provide written proof of such insurance coverage
            upon the request of Vendor.

      3.2   WARRANTY SUPPORT. NSC will provide no warranty support or support of
            any kind to any users of this Equipment. NSC is not responsible for
            management of defective returns or any other type of end user
            returns.

      3.3   LICENSING BY NSC OF ITS TECHNOLOGIES. Vendor may issue its own
            Purchase Orders in Order to license NSC technologies. Such Purchase
            Orders shall not be binding until signed by an officer of NSC.

4.    CONFIDENTIALITY. Each party agrees not to disclose to any third party the
      terms of this Contract (other than in general summary press release form
      announcing this agreement, and as otherwise required under law for
      disclosure) and any other information of the other party designated as
      confidential ("Confidential Information") and also agrees not to use any
      Confidential Information of the other party except as expressly permitted
      under this Contract or except with the prior written consent of the other
      party. Each party agrees to exercise the highest degree of care in
      safeguarding the Confidential Information of the other party against loss
      or other inadvertent disclosure.

5.    LIMITATION OF LIABILITIES. IN NO EVENT WILL NSC BE LIABLE TO VENDOR OR TO
      ANY THIRD PARTY FOR INCIDENTAL, INDIRECT, EXEMPLARY, SPECIAL OR
      CONSEQUENTIAL DAMAGES, WHETHER FORESEEABLE OR UNFORESEEABLE, ARISING OUT
      OF OR OTHERWISE RELATING TO THIS CONTRACT. IN NO EVENT WILL ANY LIABILITY
      TO NSC EXCEED THE PURCHASE PRICE PAID BY NSC.

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6.    [MISSING COPY]

      6.1   Expiration; Termination for Convenience. This Contract shall remain
            in effect for a term of two years unless earlier termination by
            either party for convenience upon 90 days prior written notice.

      6.2   Termination by BSC for Breach. NSC, at its sole option, and
            reserving all other rights and remedies available to it at law or in
            equity, shall have the right to terminate this Contract or any
            accepted Order not then completed by giving written notice of
            termination to Vendor of the occurrence of, but not limited to, any
            of the following:

            (a)   Vendor's failure to perform any material obligation set forth
                  in this Contract or any accepted Order not then completed, if
                  such failure has not been corrected within ten days after NSC
                  has given Vendor written notice of such failure; or

            (b)   Any act or event whereby Vendor (i) is or becomes insolvent,
                  (ii) is or becomes a party to any bankruptcy or receivership
                  proceeding or any similar action affecting the financial
                  condition or property of Vendor.

      6.3   Termination by Vendor for Breach. Vendor, at its sole option and
            reserving all other rights and remedies available to it at law or in
            equity, shall have the right to terminate this Contract or any
            accepted Order not then completed by giving written notice of
            termination to NSC of the occurrence of any of the following:

            (a)   NSC's failure to pay to Vendor any charge, cost, or other
                  payment accruing under any accepted Order, if such delinquency
                  has not been corrected within thirty days after Vendor has
                  given NSC written notice of such delinquency;

            (b)   NSC's failure to perform any other material obligation set
                  forth in this Contract or any accepted Order, including any
                  act of repudiation or wrongful rejection of the Equipment, if
                  such failure has not been corrected within thirty days after
                  Vendor has given NSC written notice of such failure; or

            (c)   Any act or event whereby NSC (i) is or becomes insolvent, (ii)
                  is or becomes a party to any bankruptcy or receivership
                  proceeding or any similar action affecting the financial
                  condition or property of NSC.

7.    General Provisions

      7.1   Force Majeure. Neither party shall be liable for any delays in
            performance (other than obligations for the payment of money) due to
            acts of God, war, riots, strikes, industrial or labor disputes,
            delays in transit, or any other cause, whether similar or
            dissimilar, beyond such party's control and without its fault or
            negligence. Each party will use its best efforts to notify the other
            party in writing as soon as it has knowledge that any such delays
            may occur, but such party shall not be liable for any failure to
            give such notification. Any agreed-upon schedule shall be extended
            for a period of time equal to the period of delay.

      7.2   Entire Contract. This Contract, the attached Schedules and any
            accepted Orders contain the entire Contract between NSC and Vendor
            with respect to the subject matter of this Contract. All prior
            representations, demonstrations, arrangements or understandings are
            superseded by this Contract. In particular, there are no
            representations or warranties not expressly set forth in this
            Contract.

      7.3   Non-Solicitation. Vendor shall not induce or attempt to influence,
            directly or indirectly, any employee or agent or partner of NSC to
            terminate his or her relationship or employment with NSC or to work
            for Vendor or any other person, and will not hire any employee of
            NSC during the performance of any Services for a period of one year
            after termination of this Contract.

      7.4   Governing Law. This Agreement shall be governed in accordance with
            the laws of the state Arizona and those of the United States of
            America, except that the provisions of the United Nations Convention
            on International Sale of Goods the and United Nations Convention on
            Statutory Limitations will not apply. This Agreement may be
            translated into a language other than English, but this English
            version of the Agreement shall control the rights and obligations of
            the parties regardless of any subsequent of any subsequent
            translation and regardless of any reliance by any party upon such
            translation. All communications and notices related to this
            Agreement shall be in English, and all transaction shall be in U.S.
            dollars unless otherwise specified.

      7.5   Counterparts and Modification. Any representations purporting to
            waive, vary, modify or supplement the terms of this Contract shall
            be of no force or effect unless in writing and signed by a
            duly-authorized officer of NSC and Vendor. This Contract may be
            executed in one or more counterparts, all of which together shall
            constitute one complete Contract.

      7.6   Notification. Unless otherwise provided in this Contract, any notice
            or communication required or permitted to be given to either party
            shall be in writing and shall be considered effective when received
            in the mail (postage prepaid, certified with return receipt
            requested), by facsimile or by courier at the address shown on page
            1 of this Contract for the party to be notified, unless such party
            has notified the sender in writing of a change of address, in which
            case notice shall be mailed as described above, to the revised
            address.

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