Document:

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EXHIBIT 10.20

                            INGEN TECHNOLOGIES, INC.

                            STOCK PURCHASE AGREEMENT

THIS STOCK PURCHASE AGREEMENT (The "Agreement") is made and entered into this
15th day of October, 2004; by and between KHOO Yong Sin (the "Purchaser"), a an
Individual representing various investment groups, having its principal
offices/location at No. 21 Upper Weld Road, Singapore 207378, and Ingen
Technologies. Inc. (the "Seller", "Ingen" or the "Company"), a Goergia
corporation, having its corporate headquarters at 285 E. County Line Rd.,
Calimesa CA 92320;

                              W I T N E S S E T H:

         WHEREAS, the Seller has the authority to issue 5,000,000 shares (five
Million shares) of the Company's public common stock that is Registered and
Restricted under SEC Rule-144; and

         WHEREAS, the Seller is in the business of developing, manufacturing,
marketing and selling medical and commercial products; and

         WHEREAS, the Seller is desirous of selling shares of its common stock
at negotiated prices to sophisticated and knowledgeable investors for the
purpose of raising working capital and expanding its business in accordance with
its business plan; and

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         WHEREAS, the Purchaser is representing various investors and interested
in purchasing common shares of the Company's stock in accordance with the terms
and conditions set forth herein,

         WHEREAS, the parties hereto desire to set forth in writing their
understandings and agreements;

NOW, THEREFORE, in consideration of the following premises, representations,
warranties, covenants, and for other good and valuable consideration, the timely
receipt and sufficiency of which are hereby acknowledged, the parties hereto,
intending to be legally bound, agree as follows:

1.       Sale of Shares
         --------------

Pursuant to the terms contained in this Agreement, the Purchaser hereby agrees
that it will tender the purchase price (the "Purchase Price") of $0.05 (Five
Cents) to buy up to 5,000,000 (Five Million) shares (the "Shares") of public
common stock issued by the Company and Restricted under Rule-144 pursuant to the
purchase schedule in Exhibit-A and made a part hereof. The total amount of
purchase being $ 250,000 (Two Hundred Fifty Thousand Dollars). This sum shall be
tendered in certified funds (cashier check or bank draft) and/or a wire transfer
to the bank account of the Company pursuant to the payment schedule attached and
made a part of herein as Exhibit-A. With the simultaneous payment and delivery
of the Purchase Price by the Purchaser to the Company, the Seller shall issue
and deliver to the Company immediate tender for the said shares of common stock
referenced herein for value of the purchase amount received by the Purchaser.
The Company shall be responsible for assuring that the purchased shares are duly
recorded with the Stock Transfer Agent referred to as Executive Registrar and
Transfer Agency, Inc., located in Englewood, Colorado, and as fully assessable
and paid stock in the corporate stock register and with the records of the
Company's stock transfer agent. Said event shall hereinafter be known as the
"Closing."

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All parties further acknowledge that they have had the opportunity to hire
counsel of their own choosing to serve as counselors and advisors in this
transaction.

2.       Representations and Warranties of Seller.
         -----------------------------------------

As a material inducement to Purchaser to enter into this Agreement, Seller
hereby makes the following representations and warranties, effective as of the
date hereof and AT Closing;

(a) The execution and delivery of this Agreement and the consummation of the
transaction contemplated hereby does not, and as of Closing shall not, violate
any provision of any existing law or regulation, or any mortgage, indenture,
security agreement, contract, or other agreement to which Seller is a party.

(b) Seller has the full, absolute, and entire power and legal rights to execute,
deliver and perform this Agreement and to consummate the transaction
contemplated hereby.

(c) The Shares to be sold to Purchaser are free and clear of all liens and other
encumbrances.

(d) Each share sold by the Seller to the Purchaser pursuant to this Agreement
shall be a validly issued, fully paid and nonassessable share of unrestricted
common stock of the Corporation.

(e) The Company is a corporation duly incorporated, organized, validly existing
and in good standing under the laws of its' jurisdiction of incorporation and
the Company has the requisite corporate power to carry on its business as now
being conducted.

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(1) The Seller makes no warranties and representations whatsoever, whether
express or implied, either directly or indirectly, pertaining to the market
value of the Shares or the Company. The Purchaser's decision to buy the Shares
referenced herein are the result of the Purchaser's own due diligence, research
and investigation. The Purchaser acknowledges that it has been advised by the
Company that there currently exists no public market for the sale of its Shares,
The value of the Company and its equities will in the future depend upon
circumstances that are, in many instances, within the control of the Company or
its officers and directors. These factors include, but are not limited to, the
public's perception of and need for the Company's products, the types and prices
of competing products, AND the ability of the Company to implement its business
plan.

3.       Representations and Warranties of Purchaser
         -------------------------------------------

As a material inducement to Seller to enter into this Agreement, Purchaser
Hereby make the following representations and warranties, effective as of the
date hereof and at Closing:

(a) The execution and delivery of this Agreement and the consummation of the
transaction contemplated hereby does not, and as of Closing shall not violate
any provision of any existing law or regulation, or any mortgage, indenture,
security agreement, contact, or other agreement to which Purchaser is a party.

(b) Purchaser has the full, absolute, and entire power and legal right to
execute, deliver and perform Ibis Agreement and to consummate the transaction
contemplated hereby.

(c) Purchaser has sufficient knowledge and experience in investing in companies
similar to the Corporation, in terms of the Corporation's stage of development,
so as to be able to evaluate the risks and merits of its investment in the
Seller's Shares, and it is able financially to bear the risks thereof

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(d) Purchaser has undertaken all due diligence which it deemed necessary or
appropriate and, in furtherance thereof, has had an opportunity to discuss with
the Seller all material aspects and conditions of the Corporation, including the
management and financial affairs of the Corporation, and to obtain information
and examine all documents relating to the Corporation. All questions asked by
the Purchaser have been answered to its full satisfaction, and all information
and documents, records and books pertaining to this investment the Purchaser has
requested have been made available to it.

(e) The Shares being purchased by Purchaser are being provided to various
investors, and as such the Purchaser shall provide instructions to the Seller
regarding issuing the shares in each of the names of the investors. The
Purchaser shall provide the Seller the name in which the certificate should be
issued, the amount of shares to be issued, the address and tax identification of
the name in which the shares are to be issued.

(f) Purchaser understands that the Seller is a public company. Accordingly,
Purchaser understands and acknowledges that the Shares are registered under the
Securities Act of 1933 (the "Act") pursuant to Section 4(2) thereof or Rule 505
and Rule 506 promulgated under the Act.

(g) Purchaser recognizes that an investment in the Shares involves a degree of
risk, and it is fully cognizant of and understands all of the risk factors
related to the purchase of the Shares, and Purchaser has negotiated the terms
and conditions of this Agreement in consideration thereof.

(h) Purchaser warrants and represents that it has had the opportunity to retain
counsel of its' own choosing to advise it and to review and negotiate the terms
and conditions of this transaction.

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4.       Conditions Precedent to the Obligations of Purchaser.
         -----------------------------------------------------

All obligations of Purchaser to close on the sale and purchase pursuant to this
Agreement shall be subject to the following conditions:

(a) The Seller shall deliver to the Transfer Agent within the time stipulated in
this Agreement the certificates representing the Shares.

(b) The Stockholders of the Corporation representing a majority of shares
authorized and issued shall consent to the execution by Seller of this
Agreement.

(c) In the event that the Purchaser is not able to meet or complete the Purchase
Schedule in Exhibit-A, the Seller may terminate this Agreement by serving
written notice to the Purchaser and the termination shall be effective seven (7)
days from the date of said written notice. Upon termination, either party shall
not have any claims against the other party.

5.       Expenses.
         ---------

Each party hereto shall pay its own expenses in connection with the transaction
contemplated hereby, whether or not such transaction shall be consummated.

6.       Brokerage.
         ----------

Each party hereto will indemnify and hold harmless the other from and in respect
to any claim for brokerage or other commissions relative to this Agreement or to
the transactions contemplated hereby, based in any way on agreements,
arrangements or understandings made & claimed to have been made by such party
with any third party.

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7.       Assignability.
         --------------

This Agreement and the burdens and benefits hereunder are not assignable by
either party without the prior written consent of the other party. The Seller
understands that the Purchaser is representing various investors, and therefore
the Seller authorizes the Purchaser to provide instructions regarding the name
in which each share certificate should be issued. The Purchaser will represent
each of his investors under the terms and conditions herein.

8.       Notices.
         --------

All notices, requests, consents and other communications hereunder shall be in
writing and shall be delivered in person or by overnight courier (with proof of
receipt requested) or mailed by certified or registered mail, return receipt
requested, addressed as follows:

(a) If to the Seller, to Scott Sand, Chairman of Ingen Technologies, Inc.

(b) If to the Purchaser, to or at such other address or addresses as shall have
been furnished by one party to the other in the manner specified in this
paragraph 8.

9.       Governing Law.
         --------------

This Agreement shall be governed by and construed in accordance with the laws of
the State of Georgia without giving effect to the conflict of law provisions
thereof.

10.      Headings.
         ---------

The descriptive headings of the several provisions and sections of this are
inserted for convenience only and do not constitute a part of this Agreement.

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11.      Entire Agreement.
         -----------------

This Agreement including the Exhibits hereto constitutes the entire agreement of
the parties with respect to the subject matter hereof. All Exhibits hereto are
incorporated herein by reference.

12.      Counterparts.
         -------------

This Agreement may be executed in two or more counterparts, each of which shall
be deemed an original, but all of which together shall constitute one and the
same instrument.

13.      Changes and Waiver.
         -------------------

No change or modification of this Agreement shall be valid unless the same is in
writing and signed by all parties. No waiver of any provision of this Agreement
shall be valid unless in writing and signed by the person against whom the
provision is sought to be enforced. The failure of any party at any time to
insist upon strict performance of any condition, promise, agreement or
understanding set forth herein shall not be construed as a waiver or
relinquishment of the right to insist upon strict performance of the same or any
other condition, promise, agreement or understanding at a future time.

14.      Survival of Representations and Warranties.
         -------------------------------------------

All of the representations and warranties contained in this Agreement shall
survive (i) the execution of this Agreement and any other documents related
thereto and (ii) the transfer of the Shares to the Escrowee and ultimately to
the Purchaser and shall not be merged therein.

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15.      Invalid Provisions.
         -------------------

Should any portion of this Agreement be declared invalid or unenforceable for
any reason, it shall be modified and adjusted rather than voided, if possible to
achieve the material intent of the parties. Any invalidity of any provision of
this Agreement shall not affect any other provisions of this Agreement, which
shall be deemed enforceable and valid to the maximum extent possible.

16.      Facsimiles.
         -----------

Facsimile or email transmissions of this Agreement, when duly executed by the
parties or their authorized representatives shall be as effective and legally
binding as executed originals of this Agreement.

17.      Exhibits to the Agreement.
         --------------------------

The following documents have been provided to the Purchaser and shall be deemed
to be part of this Agreement and are furnished by the Seller to the Purchaser to
inform it of the Company's activities and plans.

i)       Corporate Charter
ii)      Certificate of Good Standing
iii)     Financial Statement
iv)      Tax Returns
v)       Patents & Trademarks

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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement on
the year and date first written above.

          Purchaser:

          /S/ KHOO Yong Sin                                    October 15, 2004
          -------------------------------------------          ----------------
          KHOO Yong Sin                                              Date
          No. 21 Upper Weld Road
          Singapore, 207378
          Tel: +65 9746 8288

          Ingen Technologies, Inc.

          /S/ SCOTT R. SAND                                    October 15, 2004
          -------------------------------------------          ----------------
          Scott R. Sand, Chairman and CEO                            Date

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                                    EXHIBIT-A

PURCHASE SCHEDULE:

The Purchaser agrees to pay $50,000 on or before November 15, 2004

The Purchaser agrees to pay $100,000 on or before December 15, 2004

The Purchaser agrees to pay $100,000 on or before January 15, 2005

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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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