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                                                                    EXHIBIT 10.3


                        NATIONAL SCIENTIFIC CORPORATION

                      MASTER PURCHASE & LICENSING CONTRACT

                           CONTRACT NUMBER: NSC-KR102


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

By and Between
<TABLE>
<S>                                             <C>
Name:      Maroo Electrotech Co. Ltd.,           Name:      National Scientific Corporation
           (Korean Company)                                 (a Texas State U.S. corporation)
Address:   #138. Donghyun-RI. Koduck-Hyun        d/b/a      NSC
           PyongTaek-SI        Kyonggi-D0                   4455 E. Camelback Rd. E-160
           Korea                                            Phoenix, AZ 85018 USA
Telephone: (+)82-31-669-2560                     Telephone: 602-954-1492
Fax:       (+)82-31-667-1193                     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,
     acknowledgment 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.

VENDOR                                  NSC
  By:    /s/ Han Sang Chung               By:    /s/ Michael A. Grollman
  Name:  Han Sang Chung                   Name:  Michael A. Grollman
  Title: Vice president                   Title: C.O.O., Executive VP
  Date:  1-12-2001                        Date:  1-12-2001

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                              TERMS AND CONDITIONS

1.  PRICES; TAXES; PAY

     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 or 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 in 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 to 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 Contracts
    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 FORSEEABLE OR UNFORSEEABLE, 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 NSC 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 of Arizona and those of the United States of
          America, except that the provisions of the United Nations Convention
          on International Sale of Goods and the 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 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
          transactions 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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