<PAGE>

Exhibit 10.39

INGEN TECHNOLOGIES, INC.
285 E. County Line Road, Calimesa California 92320
(800) 259-9622     FAX: (800) 777-1186


                              CONTRACTING AGREEMENT

This Agreement made effective as of this 10th day of March, 2006, by and between
Michael Koch, DC, an individual and licensed Chiropractor, further referred to
as the ("Contractor"), whose principal address is 1815 Winola Court, Naperville,
IL 60565; and Ingen Technologies, Inc., A Nevada Corporation, further referred
to as the ("Company"), whose principal address is 285 E. County Line Road,
Calimesa, California 92320, and is made with reference to the following.

                                    RECITALS

A.   The Company is a Medical Device Manufacturer, and in the business of
     providing medical products and services on a Global basis. Said products
     and services are inclusive of, but not limited to, vestibular function
     testing and balance testing referred to as Secure Balance(TM).

B.   The Company desires to engage the services of the Contractor to be a member
     of the Advisory Board and provide professional evaluations of the Company's
     Secure Balance(TM) program as described in Exhibit-A. The Contractor is a
     licensed Chiropractor in the State of Illinois, and specializes in
     chiropractic sciences and health care. The Contractor also agrees to market
     the Secure Balance(TM) program to his peers, if and when desired.

C.   The Contractor has the expertise, knowledge and resources for development
     and implementation of the services described in Exhibit-A.

D.   The Company will provide product, installation, training, market
     assistance, promotional materials and other developmental documentation
     used to promote said products and services in accordance to all laws of
     which govern the Company in this type of industry.

E.   The Company desires to utilize the Contractor's expertise, knowledge and
     other resources for providing professional opinions and evaluations of the
     Secure Balance(TM) program.

NOW, THEREFORE, the Parties mutually agree as follows:

1.   In consideration of the Contractor furnishing the expertise, knowledge and
     other resources in providing said services as set forth in the above
     Recitals hereof, the Company agrees to issue 100,000 Shares of restricted
     stock that is Restricted under SEC Rule-144. The Company will pay the
     Contractor $500 per incident to participate Advisory Board teleconferences,
     material reviews and meetings. Said meetings will take place via telephone
     conference between the Company and the Contractor, and said meetings will
     be scheduled within the convenience of the Contractor.

2.   Although the Contractor is not obligated to discuss or promote the Secure
     Balance(TM) program, the Company authorizes the Contractor to discuss,
     promote and market the products and services of the Company as described in
     Exhibit-A. Any other products and services offered by the Company are not a
     part of this Agreement and may not be sold and/or marketed by the
     Contractor without the written permission or authorization from the
     Company.

<PAGE>

3.   As a part of the services specified herein, the Contractor accepts the
     above considerations and understands her rights to provide said services
     within the United States. The Contractor agrees to provide her "best
     efforts" to deliver those services as described in the above recitals.

4.   The Contractor is only responsible to provide advice as an Advisory Board
     Member. The Company is responsible to provide all information,
     installation, training and support to the customer. The Company holds
     harmless the Contractor from all responsibility for all liabilities and
     malpractice associated in providing any advice regarding vestibular
     function testing and balance therapy.

5.   Except for the amounts paid to the Contractor as stated in paragraph-1 and
     within the Recitals herein, the Contractor shall not be entitled to other
     payment and/or reimbursement for expenses incurred pursuant to this
     Agreement. All costs and expenses incurred by the Contractor in rendering
     said services shall be reimbursed or advanced by the Company only upon
     written authorization to the Contractor by the Company.

6.   The Company agrees to provide full and proper assistance to the Contractor
     inclusive of administrative support, technical support, and professional
     support on a best efforts basis and within regulatory guidelines and laws
     set forth for providing said services and without penalty to the
     Contractor.

7.   The Contractor agrees to provide the Company with proper tax documentation
     and identification upon the signing of this Agreement in accordance to
     State and Federal tax laws.

8.   The relationship between both parties created by this Agreement is that of
     principal ("the Company") and Outside Contractor ("the Contractor") in that
     the time spent and the professional manner in which the services are
     performed shall solely be the responsibility of the Contractor. However,
     the Contractor agrees to use their best and most diligent efforts, within
     all laws, to provide the resources and expertise under the terms and
     conditions setforth herein.

9.   During the term of this Agreement the Contractor has the right to promote
     services, either directly and/or indirectly, to any entity and/or
     competitor that has a similar products as provided by the Company for the
     duration of this Agreement.

10.  In consideration of the importance of confidentiality, non-disclosure and
     trade secrets, the Contractor acknowledges that during the course of this
     Agreement between the Company and the Contractor, the Contractor has had
     access to and will continue to have access to various confidential
     information and trade secrets consisting of compilations of information,
     records, specifications and trade lists, which are owned by the Company and
     which are regularly used in the operation of the Company's business. The
     Contractor specifically agrees to NOT distribute the product pricing of the
     Company, nor use the brand name on any of their pricing to their clients.
     Further, the Contractor will agree to keep confidential all material
     related to or made a part of this Agreement from any client, employee,
     associate and/or the like.

     In consideration of continued engagement through this Agreement during the
     period of the Agreement by the Company, the Contractor shall not disclose
     any of the aforesaid confidential information or trade secrets, directly or
     indirectly, nor use them in any way, either during the term of this
     Agreement or at any time thereafter, except as required in the Contractor's
     engagement with the Company, but does not include information already
     within the public domain at the time the information is acquired by the
     Contractor, or information that subsequently becomes public through no act
     or omission of the Contractor.


                                        2
<PAGE>

     In further consideration of continued engagement and during the period of
     the Agreement, all files, records, documents, drawings, specifications,
     equipment and similar items relating to the business of the Company,
     whether prepared by the Contractors or otherwise, coming into the
     Contractor's possession shall remain the exclusive property of the Company
     and shall not be removed from the Company's premises under any
     circumstances whatsoever without prior written consent of the Company.

11.  This Agreement shall continue in effect for a period of two years (2-yrs),
     and may be continued thereafter only by the express mutual agreement of
     both parties. This agreement may be terminated only for cause or breech of
     any terms and conditions setforth herein.

12.  This document contains the entire Agreement of the parties relating to this
     Agreement and correctly sets forth the rights, duties and obligations of
     all parties hereto. Any prior agreements, promises, negotiations and/or
     representations not expressly set forth in this Agreement is of no force
     and effect.

13.  No waiver of any term or condition of this Agreement shall be deemed or
     construed to be a waiver of such term or condition in the future, or of any
     preceding or subsequent breach of the same or any other term or condition
     of this or any other agreement. All remedies, rights, undertakings,
     obligations and agreements contained in this Agreement shall be cumulative
     and none of them shall be in limitation of any other remedy, right,
     undertaking, obligation or agreement of either party hereto.

14.  No amendment or modification of this Agreement or of any covenant,
     condition or limitation herein contained shall be valid unless in writing
     and duly executed by the party to be charged therewith. Unless otherwise
     specifically set forth under a particular provision, any amendment or
     modification shall require the overall consent of both parties.

15.  Nothing contained in this Agreement shall be construed so as to require the
     commission of any act contrary to law, and whenever there is a conflict
     between any provision of this Agreement and any statute, law, ordinance,
     rule, order or regulation, the later shall prevail, but in such event any
     such provision of this Agreement shall be curtailed and limited only to the
     extent necessary to bring it within the legal requirements.

16.  This Agreement, and all rights and obligations contained herein shall be
     binding on and inure to the benefit of the parties hereto and their
     respective heirs, executors, legal and personal representatives, successors
     and assigns. It is also specifically agreed and understood that this
     Agreement shall be binding upon any successor-in-interest to the Company by
     way of merger, consolidation or otherwise.

17.  Any controversy arising out of or in connection with this Agreement, or any
     amendment thereof, shall be determined and settled by arbitration in
     accordance with the rules of the American Arbitration Association. The
     venue for such arbitration shall be exclusively San Bernardino County, the
     State of California, and any award rendered shall be final and binding on
     each and all of the parties thereto and their successor-in-interest, and
     judgment may be entered thereon in any court having jurisdiction thereon.
     In any such proceeding, the Arbitrator shall be and hereby is empowered to
     render an award directing specific performance. Each individual party shall
     take responsibility for obligations pertaining to costs associated with
     their own legal representation.

18.  All notices among the parties hereto shall be in writing and shall be
     deemed duly served when personally delivered to another party or, in lieu
     of such personal service, when deposited in the United States mail,
     certified and return receipt requested, with first class postage prepaid
     thereon, addressed as set forth above, or in such other place as may be
     specified in any written notice given pursuant to this paragraph as the
     address for service of notice. All notices shall be delivered to the
     parties addresses as witnessed below.


                                        3
<PAGE>

                Company:        Scott Sand, CEO & Chairman
                                Ingen Technologies, Inc.
                                285 E. County Line Rd.
                                Calimesa, CA 92320
                                (800) 259-9622
                                (909) 790-7180
                                (800) 777-1186 fax
                                Tax ID No. 88-0429044

                Contractor:     Michael Koch, DC
                                1815 Winola Court
                                Naperville, IL 60565
                                630-420-8759
                                630-364-5759 fax

19.  This Agreement shall be governed and construed in accordance with laws of
     the State of California.

     IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of
     the date first set forth above and agree to all of the terms and conditions
     of this Agreement setforth herein.


     The Contractor:
                                - s -                      March 10, 2006
                       -------------------------------     ---------------
                       Michael Koch, DC                         Date


     The Company:
                                - s -                      March 10, 2006
                       -------------------------------     ---------------
                       Scott Sand, CEO                          Date

<PAGE>

<TABLE>
                                                EXHIBIT-A

                                      Product List Sold to Customer

ITI Ingen Technologies, Inc.                                   Proforma Invoice
285 E. County Line Road
Calimesa CA 92320
(800) 259-9622


Item     QTY      Part No.          Description                                           PRICE
--------------------------------------------------------------------------------------------------------
<S>      <C>      <C>               <C>                                                 <C>
1        1ea.     Model-4000D       Full Clinical 2-Channel VNG                         $39,900.00
                                    Complete with computer system,
                                    1-Camera Goggle, Footswitch, hand remote
                                    Projection Fullfield Oculomotor System
                                    Secure Balance(TM) Full Clinical VNG Software
                                    Atmos Air Irrigator and Scope
                                    Tower Computer or Laptop Lunchbox Style
                                    HP Color Printer
                                    Medical Cart

2        1ea.     Model-4000        SPORTKAT Balance System                             $17,900.00
                                    Balance Therapy & Assessment Platform
                                    VVP Computer Data System
                                    Secure Balance(TM)  Software 4.00
                                    Flat Panel Display Computer System
                                    Base Unit 360 Degree Platform w/Tilt Sensor
                                    Handrails with Gauge Readout PSI
                                    DC-Power Supply

3        1ea.                       Full Warranty 1-Year/Extended Warranty Available
                                    Software Upgrades - No Charge
                                    Technical Support-Life time
                                    2-Day Certified Installation and training (On-Site).
                                    2-Day Clinical Workshop-Jacksonville, Fl.
                                    5 Hours of Billing Consulting
                                    60 days Clinical Interpretations

4        1ea.                       Freight                                             $    465.47

Grand Total                                                                             $ 58,265.47
                                                                                        ===========

                                            TAX NOT INCLUDED
========================================================================================================
      50%Deposit/50% Delivery               FOB: Calimesa CA             Delivery: 1-2 Weeks ARO
========================================================================================================
</TABLE>