EXHIBIT 10.40

                        Addendum to the Vendor Agreement
                                     Between
              Best Buy Purchasing, LLC and SLS International, Inc.

Effective Date:   December 1, 2005
                -------------------------------------

THIS ADDENDUM TO THE VENDOR AGREEMENT (the "Addendum") is made and entered into
by and between Best Buy Purchasing LLC, a Minnesota corporation ("Best Buy"),
having its principal office at 7601 Penn Avenue South, Richfield, Minnesota,
55423, U.S.A., and SLS International, Inc., a corporation organized under
Delaware law ("Vendor"), having its principal office at 1650 W. Jackson, Ozark,
MO 65721.

WHEREAS, the parties entered into that Vendor Agreement dated December 1, 2005
(the "Vendor Agreement") pursuant to which Best Buy will purchase goods from
Vendor, and distribute, market and resell those goods;

WHEREAS, the parties entered into that certain Consignment Agreement dated
February 22, 2006 (the "Consignment Agreement") pursuant to which Best Buy will
distribute, market and resell Vendor's goods on a consignment basis;

WHEREAS, the parties desire to amend the Vendor Agreement as set forth below;

NOW, THEREFORE, in consideration of the foregoing and the mutual covenants set
forth below, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereby agree as
follows:

1. The Vendor Agreement, the Consignment Agreement, and the respective terms,
provisions and definitions thereof shall continue in full force and effect and
are hereby incorporated herein in their entirety by this reference hereto.
Unless otherwise defined herein, each capitalized term used herein that is
defined in the Vendor Agreement and/or the Consignment Agreement shall have the
meaning specified for such term in the such Agreement. Any references to
sections in this Amendment correspond to sections in the Vendor Agreement only.
Provided however, that the sales calculation processes as outlined in the
Consignment Agreement shall be used to calculate units sold. Only after Best Buy
has recorded net sales of the initial three thousand ninety units, will Best Buy
begin remitting payment for remaining units under the Consignment Agreement.

2. The parties agree that the Initial Shipment of Vendor's Products to Best Buy
shall be subject solely to the terms and conditions of the Vendor Agreement, and
that the terms and conditions of the Consignment Agreement shall not apply to
the Initial Shipment.

3. For purposes of this Addendum, "Initial Shipment" shall mean 3,090 units of
Vendor's Products set forth in a purchase order issued Best Buy on or before
March 1, 2006.

4. Best Buy shall pay Vendor's invoice for the Initial Shipment within 30 days
after delivery of the Initial Shipment.

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5. This Addendum supplements and modifies the Vendor Agreement and the
Consignment Agreement. Except as expressly modified herein, the Vendor Agreement
and the Consignment Agreement remain in full force and effect in accordance with
their respective terms and conditions. If there is any conflict between the
terms of this Addendum and the Vendor Agreement or the Consignment Agreement,
the terms of this Addendum shall control.

         IN WITNESS WHEREOF, the parties hereto have executed this Addendum as
of the day first written above.

BEST BUY PURCHASING LLC                         SLS INTERNATIONAL, INC.


By:                                             By:
    ---------------------------                     ---------------------

Title: VP- Vendor Management                    Title: President

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