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                                                                   EXHIBIT 10.15

                             NOTE PURCHASE AGREEMENT

         AGREEMENT made as of September 30, 2002 among Bostrom Holding Inc., a
Delaware corporation (the "Company"), Baird Capital Partners II Limited
Partnership, BCP II Affiliates Fund Limited Partnership, Baird Capital Partners
III Limited Partnership, BCP III Special Affiliates Limited Partnership, BCP III
Affiliates Fund Limited Partnership, Norwest Equity Partners VII, LP and Hidden
Creek Industries (the foregoing Persons other than the Company being
collectively referred to herein as the "Purchasers" and individually as a
"Purchaser"). Except as otherwise indicated, capitalized terms used herein are
defined in paragraph 8 hereof.

         The Purchasers and the Company are entering into this Agreement for the
purpose of providing financing to the Company.

         The parties hereto agree as follows:

         1. Authorization of the Notes. The Company will authorize the issuance
and sale to the Purchasers of Subordinated Promissory Notes in the aggregate
principal amount of up to $2,500,000 substantially in the form attached hereto
as Exhibit A (the "Notes").

         2. Closing of Purchase and Sale.

         2A. Purchase and Sale of the Notes. At the Closing, the Company will
sell to each Purchaser and, subject to the terms and conditions set forth
herein, each Purchaser will purchase from the Company the principal amount of
Notes as set forth opposite such Purchaser's name on the "Schedule of
Purchasers" attached hereto at a price as set forth opposite such Purchaser's
name on the Schedule of Purchasers.

         2B. The Closing. The closing of the separate purchases and sales of the
Notes to the Purchasers (the "Closing") will take place at the offices of
Kirkland & Ellis, 200 East Randolph Drive, Chicago, Illinois 60601, at 10:00
a.m. on September 30, 2002 or at such other place or on such other date as may
be mutually agreeable to the Company and each Purchaser. At the Closing, the
Company will deliver to each Purchaser the Note to be purchased by such
Purchaser at the Closing, in such Purchaser's name or the name of such
Purchaser's nominee, upon payment of the purchase price thereof by a cashier's
or certified check, or by wire transfer of immediately available funds, in the
amount set forth opposite such Purchaser's name on the Schedule of Purchasers.

         3. Conditions of Each Purchaser's Obligation. The obligation of each
Purchaser to purchase and pay for the Note at the Closing, as the case may be,
is subject to the satisfaction as of the Closing of the following conditions:

         3A. Consents. The Company will have provided each Purchaser (A)
certified copies of the (i) resolutions duly adopted by the Company's board of
directors authorizing the transactions contemplated herein, (ii) Company's
organizational documents and (iii) a certificate of good standing of the Company
certified as of a recent date by the Secretary of State of the


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State of Delaware and (B) a fully-executed copy of a waiver and consent to the
transactions contemplated herein from the lenders under that certain Credit
Agreement, dated as of March 31, 2000, among the Company, CVCS Holdings, Inc.,
the Lenders party thereto and Bank of America, N.A., as administrative agent, in
form and substance satisfactory to the Purchasers.

         3B. Sale of Notes to Each Purchaser. The Company will have sold to each
Purchaser the Note to be purchased by it hereunder at the Closing and will have
received payment therefor in full.

         3C. Waiver. Any condition specified in this paragraph 3 may be waived
if consented to by each Purchaser; provided that no such waiver will be
effective against any Purchaser unless it is set forth in a writing executed by
such Purchaser.

         4. Covenants Compliance with Agreements. The Company will perform and
observe all of its obligations to each holder of the Notes set forth herein and
in the Notes.

         5. Representations and Warranties of the Company. As a material
inducement to the Purchasers to enter into this Agreement and purchase the
Notes, the Company hereby represents and warrants that:

         5A. Organization and Corporate Power. The Company is a corporation duly
organized, validly existing and in good standing under the laws of the State of
Delaware and is qualified to do business in every jurisdiction in which the
failure to so qualify would reasonably be expected to have a material adverse
effect on the financial condition, operating results, assets, operations or
business prospects of the Company. The Company has all requisite corporate power
and authority to carry on its businesses as now conducted and presently proposed
to be conducted and to carry out the transactions contemplated by this
Agreement.

         5B. Authorization; No Breach. The execution, delivery and performance
of this Agreement, the Notes and all other agreements contemplated hereby to
which the Company is a party have been duly authorized by the Company. This
Agreement, the Notes and all other agreements contemplated hereby each
constitutes a valid and binding obligation of the Company, enforceable in
accordance with its terms, except as may be limited by the equitable remedies of
specific performance, other equitable remedies or laws governing creditors'
rights generally. The execution and delivery by the Company of this Agreement,
the Notes and all other agreements contemplated hereby to which the Company is a
party, the offering, sale and issuance of the Notes hereunder and the
fulfillment of and compliance with the respective terms hereof and thereof by
the Company, do not and shall not (i) conflict with or result in a breach of the
terms, conditions or provisions of, (ii) constitute a default under, (iii)
result in the creation of any lien, security interest, charge or encumbrance
upon the Company's capital stock or assets pursuant to, (iv) give any third
party the right to accelerate any obligation under, (v) result in a violation
of, or (vi) require any authorization, consent, approval, exemption or other
action by or notice to any court or administrative or governmental body pursuant
to, the charter or bylaws of the Company, or, to the best of the Company's
knowledge, any law, statute, rule or regulation to which the Company is subject,
or any agreement, instrument, order, judgment or decree to which the Company is
subject.


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         5C. No Material Adverse Change. Since December 31, 2001, there has been
no material adverse change in the financial condition, operating results,
assets, operations, business prospects, employee relations or customer or
supplier relations of the Company.

         5D. Financial Statements. Attached hereto as the Financial Statements
Schedule is the unaudited balance sheet of the Company as of June 30, 2002 (the
"Latest Balance Sheet"), and the related statements of income and cash flows (or
the equivalent) from January 1, 2002 through June 30, 2002. Each of the
foregoing financial statements (including in all cases the notes thereto, if
any) is accurate and complete in all material respects, is consistent with the
books and records of the Company (which, in turn, are accurate and complete in
all material respects) and has been prepared in accordance with the generally
accepted accounting principles, consistently applied.

         6. Representations, Warranties and Covenants of the Purchasers. As a
material inducement to the Company to enter into this Agreement and sell the
Notes, each of the Purchasers, severally and not jointly, represents, warrants
and covenants that:

         6A. Future Disposition. The Purchaser will not, directly or indirectly,
offer, transfer, sell, assign, pledge, hypothecate or otherwise dispose of any
of the Notes, except in compliance with the Securities Act, the Securities
Exchange Act and the rules and regulations promulgated thereunder.

         6B. Power and Authority. All action on the part of the Purchaser
necessary for the authorization, execution, delivery and performance by the
Purchaser of this Agreement and the agreements referred to herein, and the
consummation of the transactions contemplated hereby and thereby, has been
taken. This Agreement and such other agreements each constitutes a valid and
binding obligation of the Purchaser, enforceable in accordance with its terms,
except as may be limited by the equitable remedies of specific performance,
other equitable remedies or laws governing creditors' rights generally. The
consummation of the transactions contemplated by this Agreement and such other
agreements is permitted under the governing documents of the Purchaser (if any)
and any laws, regulations or other restrictions applicable to investments made
by the Purchaser.

         6C. Purchaser's Investment Representations. Each Purchaser hereby
represents that it is an "accredited investor" as such term is defined in
Regulation D of the Securities Act, it is acquiring the Restricted Securities
purchased hereunder or acquired pursuant hereto for its own account with the
present intention of holding such securities for purposes of investment, and
that it has no intention of selling such securities in a public distribution in
violation of the federal securities laws or any applicable state securities
laws; provided that nothing contained herein will prevent any Purchaser and
subsequent holders of Restricted Securities from transferring such securities in
compliance with the provisions of paragraph 7 hereof. Each certificate for
Restricted Securities will be imprinted with a legend in substantially the
following form:

         "The securities represented by this certificate were
         originally issued on September ____, 2002, and have not been
         registered under the Securities Act of 1933, as amended. The
         transfer of the



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         securities represented by this certificate is subject to the
         conditions specified in the Note Purchase Agreement, dated as
         of September   , 2002 between the issuer (the "Company") and
         certain investors, and the Company reserves the right to
         refuse the transfer of such securities until such conditions
         have been fulfilled with respect to such transfer. A copy of
         such conditions will be furnished by the Company to the
         holder hereof upon written request and without charge."

         7. Transfer of Restricted Securities.

         (i) Restricted Securities are transferable pursuant to (a) public
offerings registered under the Securities Act, (b) Rule 144 of the Securities
and Exchange Commission (or any similar rule then in force) if such rule is
available and (c) subject to the conditions specified in subparagraph (ii)
below, any other legally available means of transfer.

         (ii) In connection with the transfer of any Restricted Securities
(other than a transfer described in subparagraph 7(i)(a) or (b) above), the
holder thereof will deliver written notice to the Company describing in
reasonable detail the transfer or proposed transfer, together with an opinion of
counsel which (to the Company's reasonable satisfaction) is knowledgeable in
securities law matters to the effect that such transfer of Restricted Securities
may be effected without registration of such Restricted Securities under the
Securities Act. In addition, if the holder of the Restricted Securities delivers
to the Company an opinion of counsel that no subsequent transfer of such
Restricted Securities will require registration under the Securities Act, the
Company will promptly upon such contemplated transfer deliver new certificates
for such Restricted Securities which do not bear the Securities Act legend set
forth in paragraph 6C. If the Company is not required to deliver new
certificates for such Restricted Securities not bearing such legend, the holder
thereof will not transfer the same until the prospective transferee has
confirmed to the Company in writing its agreement to be bound by the conditions
contained in this paragraph and paragraph 6C.

         8. Definitions. For the purposes of this Agreement, the following terms
have the meanings set forth below:

         "Person" means an individual, a partnership, a limited liability
company, a corporation, an association, a joint stock company, a trust, a joint
venture, an unincorporated organization and a governmental entity or any
department, agency or political subdivision thereof.

         "Restricted Securities" means the Notes issued hereunder and any Notes
issued in exchange or substitution therefore. As to any particular Restricted
Securities, such securities will cease to be Restricted Securities when they
have (a) been effectively registered under the Securities Act and disposed of in
accordance with the registration statement covering them, (b) become eligible
for sale pursuant to Rule 144 (or any similar provision then in force) under the
Securities Act or (c) been otherwise transferred and new certificates for them
not bearing the Securities Act legend set forth in paragraph 6C have been
delivered by the Company in accordance with paragraph 7(ii). Whenever any
particular securities cease to be Restricted


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Securities, the holder thereof will be entitled to receive from the Company,
without expense, new securities of like tenor not bearing a Securities Act
legend of the character set forth in paragraph 6C.

         "Securities Act" means the Securities Act of 1933, as amended or any
similar federal law then in force.

         "Securities Exchange Act" means the Securities Exchange Act of 1934, as
amended, or any similar federal law then in force.

         "Securities and Exchange Commission" includes any governmental body or
agency succeeding to the functions thereof.

         9. Miscellaneous.

         9A. Remedies. Each holder of the Notes will have all rights and
remedies set forth in this Agreement or in the Notes and all rights and remedies
which such holders have been granted at any time under any other agreement or
contract and all of the rights which such holders have under any law. Any Person
having any rights under any provision of this Agreement will be entitled to
enforce such rights specifically, to recover damages by reason of any breach of
any provision of this Agreement and to exercise all other rights granted by law.

         9B. Expenses. The Company shall pay the reasonable fees and expenses
incurred by the Purchasers in connection with the consummation of the
transactions contemplated hereby up to a maximum amount of $5,000.

         9C. Consent to Amendments. Except as otherwise expressly provided
herein, the provisions of this Agreement may be amended and the Company may take
any action herein prohibited, or omit to perform any act herein required to be
performed by it, only if the Company has obtained the written consent of the
holders of more than 50% of the outstanding principal amount of the Notes. No
other course of dealing between the Company and the holder of any portion of the
Note or any delay in exercising any rights hereunder or under the Notes will
operate as a waiver of any rights of any such holders. If the Company pays any
consideration to any holder of any portion of the Note for such holder's consent
to any amendment, modification or waiver hereunder, the Company will also pay
each other holder granting its consent hereunder equivalent consideration
computed on a pro rata basis. Notwithstanding any other provision of this
Agreement to the contrary, all amendments to this Agreement which the Company
may propose or with respect to which the Company may be requested to consent
must be authorized by a majority of the members of the Company's board of
directors before becoming effective and binding upon the Company.

         9D. Successors and Assigns. Except as otherwise expressly provided
herein, all covenants and agreements contained in this Agreement by or on behalf
of any of the parties hereto will bind and inure to the benefit of the
respective successors and assigns of the parties hereto whether so expressed or
not. In addition, and whether or not any express assignment has been made, the
provisions of this Agreement which are for any Purchaser's benefit as a


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purchaser or holder of Notes are also for the benefit of, and enforceable by,
any subsequent holder of such Notes.

         9E. Severability. Whenever possible, each provision of this Agreement
will be interpreted in such manner as to be effective and valid under applicable
law, but if any provision of this Agreement is held to be prohibited by or
invalid under applicable law, such provision will be ineffective only to the
extent of such prohibition or invalidity, without invalidating the remainder of
this Agreement.

         9F. Counterparts. This Agreement may be executed simultaneously in two
or more counterparts (including by means of telecopied signature pages), any one
of which need not contain the signatures of more than one party, but all such
counterparts taken together will constitute one and the same Agreement.

         9G. Descriptive Headings. The descriptive headings of this Agreement
are inserted for convenience only and do not constitute a part of this
Agreement.

         9H. Governing Law. All issues concerning the construction, validity and
interpretation of this Agreement and the exhibits and schedules hereto will be
governed by the internal law, and not the law of conflicts, of the State of
Delaware.

         9I. Notices. All notices, requests, demands and other communications
hereunder shall be in writing and shall be mailed by certified or registered
mail, return receipt requested and postage prepaid, or sent by reputable
overnight courier service (charges prepaid) or personally delivered (in which
case it will be deemed received when so delivered) or sent by facsimile
transmission with confirming copy sent by overnight courier (such as Express
Mail, Federal Express, etc.) and a delivery receipt obtained and addressed to
the intended recipient (in which case it will be deemed received on the next
business day following the date on which so sent). Such notices, demands and
other communications will be sent to each Purchaser at the address indicated on
the Schedule of Purchasers and to the Company at the address indicated below:

                            c/o Hidden Creek Industries
                            4508 IDS Center
                            Minneapolis, MN 55402
                            Attention: Dan Moorse
                            Telephone: (612) 766-9132
                            Telecopy: (612) 332-2012

                            With a copy to:

                            Kirkland & Ellis
                            200 E. Randolph
                            Chicago, Illinois 60601
                            Attention: John A. Schoenfeld, Esq.
                            Telephone: (312) 861-2000
                            Telecopy: (312) 861-2200


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or to such other address or to the attention of such other person as the
recipient party has specified by prior written notice to the sending party.

         9J. Understanding Among the Purchasers. The determination of each
Purchaser to purchase the Notes pursuant to this Agreement has been made by such
Purchaser independent of any other Purchaser and independent of any statements
or opinions as to the advisability of such purchase or as to the properties,
business, prospects or condition (financial or otherwise) of the Company and its
Subsidiaries which may have been made or given by any other Purchaser or by any
agent or employee of any other Purchaser.

         9K. Complete Agreement. This Agreement, those documents expressly
referred to herein and other documents of even date herewith embody the complete
agreement and understanding among the parties and supersede and preempt any
prior understandings, agreements or representations by or among the parties,
written or oral, which may have related to the subject matter hereof in any way.

                                      *****


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

                                  BOSTROM HOLDING INC., a Delaware corporation

                                  By:   /s/ [ILLEGIBLE]
                                      ------------------------------------------
                                  Its:  Vice President and Assistant Secretary
                                       -----------------------------------------

                                  PURCHASERS:

                                  Baird Capital Partners II Limited Partnership

                                  By:  Baird Capital Partners Management Company
                                       LLC

                                  Its: General Partner

                                  By:   /s/ [ILLEGIBLE]
                                      ------------------------------------------
                                  Its: Partner


                                  BCP II Affiliates Fund Limited Partnership

                                  By:  Baird Capital Partners Management Company
                                       LLC

                                  Its: General Partner

                                  By:   /s/ [ILLEGIBLE]
                                      ------------------------------------------
                                  Its: Partner



                                  Baird Capital Partners III Limited Partnership

                                  By:  Baird Capital Partners Management Company
                                       III, LLC

                                  Its: General Partner

                                  By:   /s/ C. Andrew Brickman
                                      ------------------------------------------
                                  Its: Partner
<PAGE>


BCP III Special Affiliates Limited Partnership

By:  Baird Capital Partners Management Company
     III, LLC

Its: General Partner

By:  /s/ C. Andrew Brickman
     -----------------------------------------
Its: Partner



BCP III Affiliates Fund Limited Partnership

By:  Baird Capital Partners Management Company
     III, LLC

Its: General Partner

By:  /s/ C. Andrew Brickman
     -----------------------------------------
Its: Partner



Norwest Equity Partners VII, LP

By:  Itasca LBO Partners VII, LLP

Its: General Partner

By:  /s/ [ILLEGIBLE]
     -----------------------------------------
Its: Partner



Hidden Creek Industries

By:  /s/ [ILLEGIBLE]
     -----------------------------------------
Its:
     -----------------------------------------