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                                                                   EXHIBIT 10.25


                        ADDENDUM FOR MANUFACTURING SPACE

This agreement entered into on 6/23/00, by and between Grayscale, Inc. DBA
microHelix Labs, Inc., a corporation chartered under the laws of the state of
Oregon and having it's principal offices located at 4581 S Butterfield Dr.
Tucson, AZ 85714 herein referred to as SELLER, and Agave Wire, a corporation
chartered under the laws of the state of Texas and having its principal offices
located at 10355 Sanders Dr Dallas, TX 75238 herein referred to as PURCHASER.

Whereas, Seller has contractual relationships with one or more Mexican
corporations organized under the General Corporation Law of Mexico qualified and
registered to do business under the maquiladora assembly or manufacturing
programs prescribed by the Law for the furnishing of manufacturing assembly
space (hereinafter referred to as "space"), and,

Whereas, Seller upon agreement, can furnish space the following selected
location in Nogales, Sonora, Mexico, pursuant to it's aforementioned existing
established contractual relationships in accordance with the terms and
conditions set forth below; and,

Whereas, Purchaser is desirous of using the space offered by Seller.

Therefore, it is agreed as follows:

1.      The Seller has entered into a lease agreement for manufacturing space
        located at Calle San Jose Fraccionamiento in the city of Nogales,
        Sonora, Mexico on the sole behalf of the Purchaser. This lease agreement
        has been executed between David R. Martell (representing Grayscale Inc.)
        and Harvey Featherly (representing Agave Wire). Purchaser assumes full
        responsibility for said lease terms and conditions.

2.      The space is 18464.4 Sq. Ft. (including shared common space) and is
        being leased at a rate of US $4.82 per square foot, per year for a total
        of US $89973.81 per year, payable in monthly installments on the first
        of each month. (a)

3.      The term of the lease is for 29 months and 15 days from 8/1/00 allowing
        for a prorated lease rate if applicable.

4.      The building shall be fit for occupancy at 12:01 AM on 8/1/00, per the
        terms and conditions of the lease agreement.

5.      Purchaser is responsible for all needed leasehold improvements and
        maintenance to support their manufacturing operation as detailed in
        Articles I and II of the Contractual Guideline for Shelter Program
        Relationships.

6.      Seller shall use its best effort to assist in the facilitation of the
        manufacturing space to meet the Purchaser's requirements.

7.      Purchases shall hold Seller harmless of any liabilities associated with
        the terms and conditions of the lease contract that has been executed on
        the Purchaser's behalf.

IN WITNESS WHEREOF the parties hereto have executed this Agreement, and its
associated addendum, or caused this Agreement to be executed, as of this day and
year written below:

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PURCHASER:                                     SELLER:


BY  /s/ Harvey Featherly                       By   /s/ David Martell
    ------------------------------------            ---------------------------

TITLE  President                               TITLE   General Manager
     -----------------------------------            ---------------------------

DATE  6-23-00                                  DATE   6/23/00
    ------------------------------------            ---------------------------

AGREEMENT START DATE  8-1-00
                    --------------------

monthly sublease amount (a) 89,973.81 (divided by) 12 = 7,497.82

NOGALES PLANT SUBLEASE