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EXHIBIT 10.21

        Agreement for Business Consulting between Ingen Technologies & Ed Whelan


                            INGEN TECHNOLOGIES, INC.

                          BUSINESS CONSULTING AGREEMENT

AGREEMENT, made and entered into October 15, 2004, by and between Edward T.
Whelan, Individually of Grace Holdings, Inc. a Maryland Corporation with offices
located at 135 First Street, Keyport NJ 07735 ("Grace and Whelan"), and Ingen
Technologies, Inc., a Georgia Corporation with offices located at 285 E. County
Line Road, Calimesa, CA 92320 ("CRTZ").

                              W I T N E S S E T H:

         WHEREAS, Grace and Whelan provide consultation and advisory services
relating to business management and marketing; and

         WHEREAS, CRTZ desires to utilize the services of Whelan and Grace in
connection with its operations.

         NOW, THEREFORE, in consideration of the premises and the mutual
covenants hereinafter set forth, Whelan/Grace and CRTZ hereby agree as follows:

1. CONSULTING SERVICES. Effective as of October 15, 2004, by and subject to the
terms and conditions herein contained, Grace and Whelan shall provide business
management, marketing consultation and advisory services to CRTZ. Such services
shall include (a) the preparation, implementation and monitoring of business and
marketing plans, (b) advice concerning production layout and planning and
internal controls and (c) such other managerial assistance as Whelan and Grace
shall deem necessary or appropriate for CRTZ's business.

2. PAYMENT. In consideration for the services of Grace and Whelan to be provided
CRTZ shall issue to 1,000,000 restricted CRTZ shares. The shares are to be
issued in the name and amounts as described in Exhibit-A and made a part of this
Agreement. Please have all the certificates delivered to 135 First Street,
Keyport NJ 07735. CRTZ shall in respect to each month during the term of this
agreement issue a number of restricted shares determined by dividing $6,000 by
the product of 80% and the average low price for CRTZ common stock during such
month. CRTZ shall also issue to Grace or its designee five-year options to
purchase an equivalent number of shares of our common stock at a price of 120%
of the average low price per share.

3. EXPENSES. CRTZ shall reimburse Whelan for all pre-approved travel and other
expenses incurred by it in rendering services hereunder, including any expenses
incurred by consultants when such consultants are temporarily located outside of
the metropolitan New York, area for the purpose of rendering services to or for
the benefit of CRTZ pursuant to this Agreement. Whelan and Grace shall provide
receipts and vouchers to CRTZ for all expenses for which reimbursement is
claimed.


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4. INVOICES. All pre-approved invoices for services provided to CRTZ and
expenses incurred by Whelan and Grace in connection therewith shall be payable
in full within fifteen (15) days of the date of such invoice. Payment of
invoices shall be wire to Grace Holdings, Inc. Account: 9489495934 -- ABA:
021200339 Fleet Bank, 1300 Highway 36, Hazlet, NJ 07730, 732-264-8152 or made by
check made payable to Grace Holdings, Inc. and mailed to 135 First Street,
Keyport NJ 07735 within the allotted ten (10) days.

5. PERSONNEL. Whelan and Grace shall be an independent contractor and no
personnel utilized by Whelan and Grace in providing services hereunder shall be
deemed an employee of CRTZ. Moreover, neither Whelan nor Grace nor any other
such person shall be empowered hereunder to act on behalf of CRTZ. Whelan and
Grace shall have the sole and exclusive responsibility and liability for making
all reports and contributions, withholdings, payments and taxes to be collected,
withheld, made and paid with respect to persons providing services to be
performed hereunder on behalf of CRTZ, whether pursuant to any social security,
unemployment insurance, worker's compensation law or other federal, state or
local law now in force and effect or hereafter enacted.

6. TERM AND TERMINATION. This Agreement shall be effective from October 15,
2004, and shall continue in effect for a period of 12 months thereafter. This
Agreement may be renewed for a provisional six-month period thereafter, upon
mutual agreement of the parties.

7. NON-ASSIGNABILITY. The rights, obligations, and benefits established by this
Agreement shall not be assignable by either party hereto. This Agreement shall,
however, be binding upon and shall inure to the benefit of the parties and their
successors.

8. CONFIDENTIALITY. Neither Whelan nor Grace nor any of its consultants, other
employees, officers, or directors shall disclose knowledge or information
concerning the confidential affairs of CRTZ with respect to CRTZ's business or
finances that was obtained in the course of performing services provided for
herein.

9. LIMITED LIABILITY. Neither Whelan and Grace nor any of its consultants, other
employees, officers or directors shall be liable for consequential or incidental
damages of any kind to CRTZ that may arise out of or in connection with any
services performed by Whelan and Grace hereunder.

10. GOVERNING LAW. This Agreement shall be governed by and construed in
accordance with the laws of the State of New Jersey without giving effect to the
conflicts of law principles thereof or actual domicile of the parties.

11. NOTICE. Notice hereunder shall be in writing and shall be deemed to have
been given at the time when deposited for mailing with the United States Postal
Service enclosed in a registered or certified postpaid envelope addressed to the
respective party at the address of such party first above written or at such
other address as such party may fix by notice given pursuant to this paragraph.


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12. NO OTHER AGREEMENTS. This Agreement supersedes all prior understandings,
written or oral, and constitutes the entire Agreement between the parties hereto
with respect to the subject matter hereof. No waiver, modification or
termination of this Agreement shall be valid unless in writing signed by the
parties hereto.

This Agreement may be executed in counterparts, each of who shall be deemed to
be an original, but all such counterparts shall together constitute one and the
same instrument.


IN WITNESS WHEREOF, CRTZ, WHELAN AND CRTZ HAVE DULLY EXECUTED THIS AGREEMENT AS
OF THE DAY AND YEAR FIRST ABOVE WRITTEN.


INGEN TECHNOLOGIES, INC.


/S/ SCOTT SAND
---------------------------------
SCOTT SAND, CEO & CHAIRMAN


/S/ EDWARD T. WHELAN
---------------------------------
BY:  EDWARD T. WHELAN, PERSONALLY



GRACE HOLDINGS, INC.


/S/ EDWARD T. WHELAN
---------------------------------
BY:  EDWARD T. WHELAN, PRESIDENT


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                                        EXHIBIT-A

          52-2226020                                        500,000
          Grace Holdings, Inc.
          Harbor View Unit 2-F
          135 First Street, Unit 2-F
          Keyport, NJ 07735

          52-6993865                                        250,000
          Atlantic Investment Trust
          Richard H. Tanenbaum, Esq., Trustee
          7315 Wisconsin Avenue, Suite 775 N
          Bethesda, Maryland 20814

          ###-##-####                                       250,000
          Ms. Caroline Holdridge
          3940 Becket Street
          Colorado Springs, CO 80906
                                                       -------------
                                                          1,000,000
                                                       =============


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