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                                                                     EXHIBIT 4.1

                             ENGAGEMENT AGREEMENT

February 7, 2000

Mr. David H. Dingus
President & COO
Aztec Manufacturing Co.
P.O. Box 688
400 North Tarrant
Crowley, TX 76036

1.   This letter agreement will confirm the understanding between Aztec
     Manufacturing Co. and/or its affiliates and successors (the "Company" or
     "AZZ") and RCG Capital Markets Group, Inc. and/or its affiliates and
     successors ("RCG") with respect to the matters set forth herein. RCG will
     provide consulting and other services, as more particularly described
     herein and in the attachment hereto entitled Financial Relations Services
     Attachment (the "Financial Relations Services"), to the Company and will
     represent the Company during the engagement as exclusive Financial
     Relations Consultants with respect to the Financial Relations Services, on
     the terms and conditions set forth herein and in the attachments hereto,
     all of which are incorporated herein by reference and form a part hereof.
     The period during which RCG will perform the Financial Relations Services
     for the Company will commence on February 7, 2000 (the "Commencement Date")
     and, unless otherwise terminated as provided in this paragraph or in
     paragraph nine of this letter agreement, will terminate on the date which
     is Eighteen (18) months following the commencement date (the "Termination
     Date"). The period beginning on the Commencement Date and ending on the
     Termination Date is hereafter referred to as the "Engagement Term". As more
     particularly described in paragraph 9 below, either party may terminate
     this agreement at any time after the initial Six (6) month anniversary of
     the Commencement Date upon thirty (30) days prior written notice to the
     other party. (the "Early Termination Date")

2.   During the Engagement Term, the Company agrees to furnish or cause to be
     furnished to RCG all information concerning the Company as RCG reasonably
     requests and deems appropriate for purposes of providing the Financial
     Relations Services. The Company represents that all information, with
     respect to the Company, provided to RCG will be complete and correct in all
     material respects and will not contain any untrue statement of a material
     fact or omit to state a material fact necessary in order to make the
     statements therein not misleading in light of the circumstances under which
     such statements are made. Aztec understands that in rendering the Financial
     Relations Services required hereunder, RCG will be using and relying on
     publicly available information and the information furnished to RCG by
     Aztec without independent verification thereof. RCG will treat as
     confidential any non-public information provided to it hereunder and will
     not disclose the same to third parties at any time unless required by
     applicable law. In the event disclosure has been or will be made by RCG,
     RCG will use its reasonable best efforts to cooperate as requested by the
     Company in minimizing any potential loss or injury to the Company as a
     consequence of any such necessary disclosure. In addition, RCG will use its
     reasonable best efforts to comply with all applicable state and Federal
     securities laws in the performance of this agreement.

3.   During the Engagement Term, RCG and its employees, consultants and
     contractors will be generally available to Aztec Manufacturing Co., in
     connection with its rendering of the Financial Relations Services.
     Specifically, RCG (a) will outline, develop and implement a financial
     relations program to assist the Company in creating and/or enhancing a
     positive and more visible public image, (b) may contact existing and future
     shareholders, broker/dealers, potential investors, registered
     representatives, institutions, mutual fund managers, investment banking
     sources, securities analysts, independent portfolio managers, and other
     professional investment community
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February 7, 2000
Page 2

     contacts including certain financial media sources for the purpose of
     enhancing the Company's public image and perceived value, (c) will assist
     the Company in the creation, production and distribution of certain
     financial markets and investor/shareholder corporate image materials,
     including corporate profiles, due diligence materials and investor
     packages, as well as all financial press releases; (d) assist the Company
     in its endeavor to secure research analyst coverage through a targeted
     securities professionals campaign and (e) otherwise perform the services
     described in the Financial Relations Services Attachment.

4.   During the Engagement Term, the Company will afford RCG the opportunity and
     reasonable time period to review and/or comment on any disclosure, prior to
     its release, which the Company plans to make to any of the sources
     described in paragraph (3) and which relates to the Financial Relations
     Services to be provided hereunder. In addition, RCG will be responsible for
     assisting the Company in writing and/or editing, producing, coordinating
     and disseminating all financial industry press releases. RCG agrees that it
     will not release or distribute any press release without the Company's
     prior consent.

5.   In consideration of RCG's services hereunder, the Company agrees to pay
     RCG, promptly when due, the Compensation as described by and in strict
     accordance with the attachment hereto entitled Financial Relations
     Compensation Attachment. Should RCG and the Company determine to extend the
     Engagement Term or change the scope of the engagement, then a mutually
     acceptable amendment or supplement to that attachment shall be promptly
     executed by RCG and Company. Absent any such amendment, all terms and
     conditions of this letter agreement shall be binding to the parties.

6.   RCG shall be entitled to such additional fees as may be mutually agreed
     upon by separate agreement between the parties hereto, for additional
     consulting services not anticipated in this agreement rendered during the
     engagement term.

7.   As more particularly set forth in the Financial Relations Compensation
     Attachment, the Company agrees to pay all of RCG's direct and certain
     indirect out-of-pocket expenses reasonably incurred, in connection with
     this engagement. As set forth in the Financial Relations Compensation
     Attachment, an expense retainer shall be utilized for this purpose.

8.   The Company and RCG agree to indemnify each other (the indemnifying party
     hereafter being referred to as the "Indemnitor", and the party entitled to
     indemnification hereafter being referred to as the "Indemnitee") as
     follows: Indemnitor agrees to defend, indemnify and hold harmless
     Indemnitee, and its officers, directors, and employees against any and all
     losses, claims, demands, suits, actions, judgments, awards, damages,
     liabilities, costs, reasonable attorneys' fees, and expenses incurred in
     investigating, preparing or defending any such action or claim, directly or
     indirectly caused by, related to, or asserted by a third party, based upon
     or arising out of (a) the indemnitor's breach of or the incorrectness of
     any of its representations, warranties, or covenants contained in this
     agreement; and/or (b) any Services rendered by RCG as defined in or
     contemplated by this agreement, as it may be amended from time to time (the
     "Agreement"). Notwithstanding the foregoing, the Indemnitor shall have no
     obligation to indemnify or hold the Indemnitee harmless with regard to
     Indemnitee's gross negligence, willful misconduct, or the material breach
     of or the incorrectness of any representation, warranty or covenant of
     Indemnitee contained in this Agreement.

9.   Either party hereto may terminate this engagement as follows:

     (a)  Either party hereto may terminate this agreement at the conclusion of
          Initial Six (6) months from the execution date of the agreement by
          providing the other party a 30-day advance written notification of
          "Intent to Terminate Agreement". Not withstanding the above, the
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February 7, 2000
Page 3

          Company may also terminate this Agreement after the Initial Six (6)
          months at any time "without cause", upon providing RCG Thirty (30)
          days advance written notice. In the event of a termination by the
          Company, "without cause" after the initial Six (6) months, RCG shall
          be entitled to receive Fifty (50%) percent of the remaining engagement
          term period cash compensation to the extent it is unpaid, pro-rated
          from the notice date of termination, along with reimbursement of any
          non paid, out-of-pocket expenses up to the effective date of
          termination. Additionally, RCG will be entitled to receive all
          unexercised vested, and 1/12 of the remaining non-vested warrants or
          stock options granted hereunder for each month past the initial Six
          (6) month period, up to and including the date of termination. Such
          payment is due and payable on the effective date of termination.

     (c)  WITH CAUSE: In addition, the Company may terminate this Agreement at
          any time upon written notice to RCG:

          (i)    If RCG fails to cure any material breach of any provision of
                 this Agreement within Sixty (60) days from written notice from
                 the Company (unless such breach cannot be reasonably cured
                 within the Sixty (60) days and RCG is actively pursuing to cure
                 said breach).

          (ii)   For RCG's substantial negligence, willful misconduct, fraud,
                 misappropriation, embezzlement, or other dishonesty;

          (iii)  Upon a final and conclusive judicial ruling of RCG's failure to
                 have materially complied with applicable law or regulation
                 relating to the Services it will perform;

          (iv)   Upon the filing by or against RCG of a petition to have RCG
                 adjudged as bankrupt or a petition for reorganization or
                 arrangement under any law relating to bankruptcy, and where any
                 such involuntary petition is not dismissed within 90 days.

          Upon termination under subparagraph (b) of this paragraph 9, the
          Company shall have no liability to RCG for Compensation accruing after
          such termination, and RCG shall have no further entitlement thereto.
          Upon such termination, RCG shall be entitled to receive and retain
          only accrued Compensation and vested Options to the date of such
          termination, to the extent it is unpaid, together with expenses not
          yet reimbursed.

     (c)  RCG may terminate this agreement at any time upon written notice to
          the Company.

          (i)    If the Company fails to cure any material breach of any
                 provision of this Agreement with Sixty (60) days from written
                 notice from the Company (unless such breach cannot be
                 reasonably cured within the Sixty (60) days and the Company is
                 actively pursuing to cure said breach);

          (ii)   For the Company's substantial negligence, willful misconduct,
                 fraud or misrepresentation;

          Such termination under 9(c)(i or ii) shall be deemed to be a
          termination by the Company "without cause" as provided in paragraph 9
          (a) above.

          (iii)  Upon a final and conclusive judicial ruling of Company's
                 failure to have materially complied with any applicable law or
                 regulation relating to the Services being provided;

          (iv)   Upon the filing by or against the Company of a petition to have
                 the Company adjudged as bankrupt or a petition for
                 reorganization or arrangement under any law relating to
                 bankruptcy, and where any such involuntary petition is not
                 dismissed within 90 days.
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February 7, 2000
Page 4

     (d)  RENEWAL. The Company agrees to notify RCG in writing Thirty (30) days
          prior to the end of the Eighteen (18) month period of its intent to
          not renew. Should the Company fail to notify RCG, the contract will
          revert to a month-to-month agreement until specifically renewed in
          writing or terminated with the advance Thirty (30) day notice. Such
          renewal or month-to-month engagement shall be on the same terms and
          conditions contained herein, unless modified and agreed in writing by
          both parties.

10.  RCG hereby fully discloses that certain associates, affiliates, officers
     and employees of RCG are:

     (a)  Licensed as Registered Securities Principals issued by the National
          Association of Securities Dealers ("NASD"); and/or

     (b)  Licensed as Registered Representatives issued by the NASD.

     All NASD registrations are carried by SWS Financial Services, Inc., which
     is a non-RCG affiliated NASD-registered broker/dealer.

     RCG further discloses and the Company specifically acknowledges that RCG is
     NOT a broker/dealer registered with the NASD or any other regulatory
     agency. Furthermore, in the performance of Services under the terms and
     conditions of this agreement, such services shall not be considered to be
     acting in any broker/dealer or underwriting capacity and therefore RCG is
     not receiving any compensation from the Company as such.

11.  The Company understands and acknowledges that RCG provides other and
     similar consulting services to companies, which may or may not conduct
     business and activities similar to those of the Company. RCG is not
     required to devote its full time and attention to the performance of its
     duties detailed in this agreement, and may devote only so much of its time
     and attention as it deems reasonable or necessary.

12.  As the services are being provided by an Arizona domiciled corporation, the
     validity and interpretation of this letter agreement shall be governed by
     the laws of the State of Arizona applicable to agreements made and to be
     fully performed therein.

13.  In the event of any controversy or dispute arising out of, or relating to
     this Agreement or breach thereof, RCG and AZZ agree to settle such
     controversy by arbitration pursuant to Arizona Revised Statutes, 12-1501 et
     seq. and in accordance with the rules, of the American Arbitration
     Association governing commercial transactions then existing, to the extent
     that such Rules are not inconsistent with said Statutes and this Agreement.
     Judgment upon the award rendered under arbitration may be entered in any
     court having jurisdiction. The cost of the arbitration procedure shall be
     borne by the losing party, or, if the decision is not clearly in favor of
     one party or the other, the costs shall be borne as determined by the
     arbitrator. The parties agree that the arbitration procedure provided
     herein shall be the sole and exclusive remedy to resolve any controversy or
     dispute arising hereunder, and that the proper venue for such arbitration
     proceeding shall be Maricopa County, Arizona.

14.  For the convenience of the parties, any number of counterparts of this
     letter agreement may be executed by the parties hereto. Each such
     counterpart shall be deemed to be an original instrument, but all such
     counterparts taken together shall constitute one and the same letter
     agreement.

15.  Miscellaneous:
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February 7, 2000
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(a)  Modification: This Agreement sets forth the entire understanding of the
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     parties with respect to the subject matter hereof. This Agreement may be
     amended only in writing signed by both parties.

(b)  Notices: Any notices hereunder shall be sent to the Company and RCG at
     -------
     their respective addresses set forth. Any notice shall be given by
     registered or certified mail, postage prepaid, and shall be deemed to have
     been given when received by the non-sending party. Either party may
     designate any other address to which notice shall be given, by giving
     written notice to the other of such change in address in the manner herein
     provided.

(c)  Waiver: Any waiver by either party of a breach of any provision of this
     ------
     Agreement shall not operate as or be construed to be a waiver of any other
     breach of that provision or of any breach of any other provision of this
     Agreement. The failure of a party to insist upon strict adherence to any
     term of this Agreement on one or more occasions will not be considered a
     waiver or deprive that party of the right thereafter to insist upon
     adherence to that term of any other term of this Agreement.

(d)  Relationship of the Parties: Nothing in this Agreement shall create any
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     partnership or joint venture between the parties hereto, it being
     understood and agreed that the parties are independent contractors and
     neither has the authority to bind the other in any way.

(e)  Entire agreement: This Agreement contains the entire agreement between the
     ----------------
     parties and may not be altered or modified, except in writing and signed by
     the party to be charged thereby, and supersedes any and all previous
     agreements between the parties.

If the foregoing correctly sets forth our agreement, please sign the enclosed
copy of the letter in the space provided and return it to us, whereupon all
parties will be bound to the terms of this engagement.

Confirmed and agreed to February 7, 2000


RCG Capital Markets Group, Inc.         Aztec Manufacturing Co.


By:  /s/ ILLEGIBLE                      By:  /s/ ILLEGIBLE
     ------------------------------          ------------------------------

Title:  President                       Title:  President
        ---------------------------             ---------------------------
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February 7, 2000
Page 6

                              FINANCIAL RELATIONS
                              SERVICES ATTACHMENT


     As of February 7, 2000 and by the of execution of this agreement, RCG
Capital Markets Group, Inc. and/or affiliates, (collectively "RCG") will serve
as the exclusive Financial Relations Counsel for Aztec Manufacturing Co. ("AZZ"
or "Company"). RCG anticipates the following services will be attempted and/or
implemented within the scope of this engagement:

  .  Outline, define, establish and implement a well-coordinated "Financial
     Relations" campaign.

  .  Create, produce, enhance existing and distribute high-quality, due
     diligence and marketing materials, which specifically include, but are not
     limited to a "Corporate Profile" document and the Company's "Investor
     Package".

  .  Specifically develop, proactively execute and maintain a targeted
     securities professionals telecommunications and information campaign
     specifically directed toward retail brokers, institutional investors,
     third-party portfolio managers and small/mid-cap mutual funds, buy and sell
     side analysts and the financial media as circumstances dictate, including,
     but not limited to, preparation, clearing with the Company and
     dissemination of quarterly press releases and other news releases deemed
     appropriate by the Company. RCG will allocate and utilize its proprietary
     securities industry, small/mid cap company oriented, databases and fax-line
     communications programs. (This will include responding to all incoming
     investment community inquiries and fulfillment of information and data
     requests.)

  .  RCG will attempt to secure investment recommendations and on-going
     corporate research coverage from national or regional investment banking or
     research firms and/or an endorsement by an investment newsletter
     publication.

  .  When appropriate, plan, arrange and coordinate specific follow-on road-show
     presentations to strategically targeted primary metropolitan financial
     markets.

  .  RCG will be responsible for the origination and release of financial
     industry data and financial media information on behalf of Aztec
     Manufacturing Co. RCG will also be responsible for editing (or writing) all
     press releases and coordinating information disseminated to all media
     sources relating to the securities industry and capital markets.

  .  RCG will organize, monitor and follow-up all conference calls between the
     Company and RCG's targeted segment of the investment community, in
     conjunction with material press releases, through a teleconferencing
     service. (RCG will be responsible for faxing and/or emailing the
     invitations and will follow up with calls to the recipients in an effort to
     expand the conference call participation.)

  .  Plan, arrange and coordinate periodic registered representative,
     institutional and/or other securities professionals meetings, luncheons,
     dinners or special gatherings.

  .  Implement periodic direct mailings which may include the most recent
     statistical information reports, and any appropriate articles or press
     releases that have been released during the last reported quarter.
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February 7, 2000
Page 7

  .  Update all due diligence and marketing materials. RCG anticipates updating
     Company information on a regular basis as required when there are material
     changes or events that should be disseminated to the investment community.

  .  Implement an AZZ Internet Site on RCG's Internet Home Page, RCG Online. RCG
     Online will also create an Internet link to the Company's home page. The
     purpose of these inclusions will be to provide the investment community 24-
     hour access site to obtain up-to-date information about the Company. There
     will be an additional cost of $350 per month for this service

RCG intends to perform the services and accomplish the specified goals within
the scope of this engagement. However, due to the nature and type of services
being performed, RCG cannot guarantee, nor can it be assumed that certain
specific results will be realized with reference to increased market valuation
of AZZ securities.
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February 7, 2000
Page 8

                              F1NANCIAL RELATIONS
                            COMPENSATION ATTACHMENT

In consideration of the Financial Relations Services to be rendered pursuant
hereto Aztec Manufacturing Co. agrees to promptly pay RCG the following
compensation (the "Compensation"):

(a)  Cash Compensation. During the term of this Agreement, the Company shall pay
     -----------------
     RCG a monthly fee of $6,500 payable monthly in advance of services rendered
     and beginning upon the commencement date of this Agreement (the "Retainer
     Fees").

(b)  Expense reimbursement. In addition, RCG shall be reimbursed for all direct
     ---------------------
     and certain indirect prorated out-of-pocket incurred in connection with the
     performance of the Financial Relations Services pursuant hereto. Aztec
     Manufacturing Co., will remit $5,000 to RCG, which RCG will utilize as an
     escrow deposit for the express purpose of indemnifying RCG in the event of
     late payment of monthly expenses by the Company. RCG will provide the
     Company with a detailed breakdown of all reimbursable expenses incurred in
     the previous month by approximately the Twentieth (20th) day of the
     following month of service. Aztec Manufacturing Co. agrees to reimburse RCG
     within 15 days of receipt of detailed invoice each month. If Aztec is
     delinquent in timely reimbursement of expenses as defined above, RCG will
     have the right to withdraw from the escrow account the applicable dollar
     amount to fully reimburse RCG. If reimbursement is not received by RCG by
     the 25th day after the date of the invoice, Aztec will then be immediately
     required to remit to RCG an amount equal to the expenses in question. RCG
     will then replenish the escrow account for the amount withdrawn to cover
     the delinquency. RCG can at its discretion discontinue all representation
     activities on behalf Aztec Manufacturing Co. if RCG deems Aztec to be
     routinely delinquent in the timely payment of expenses and/or the monthly
     fees as stated above. Such discontinuance does not extinguish the Company's
     obligation for reimbursement and payment of retainer fees.

     RCG will obtain prior approval from the Company for all specific expense
     items and any single miscellaneous expense item in excess of $750. RCG
     acknowledges and understands that the Company will have specific amounts
     budgeted for these expenditures and will use it's best efforts to ensure
     those budget amounts are not exceeded.

(c)  Stock Warrants/Options. Upon execution of this and subject to Board of
     ----------------------
     Directors approval, the Company will grant RCG a non-forfeitable, non-
     cancelable warrant/option (the "Warrants/Options") to acquire 70,000 shares
     of Aztec common stock of which 30% shall vest immediately and the balance
     will be subject to the performance based vesting provisions outlined below.
     The Options issued will possess a Five year expiration term and will
     provide RCG the right, until February 7, 2005, to purchase common shares of
     the Company at a price equal to the closing price of AZZ common stock as of
     the engagement agreement execution date. The Company agrees to issue an
     options/warrants document which conforms to and delineates the terms and
     conditions contained herein, within sixty (60) days of this Agreement's
     execution date. The Warrants/options will have the following vesting
     provisions:


          25% - Upon confirmation of a 30% increase (10,400 shares) in the
                average daily trading volume of the Company's stock over any 10
                consecutive trading day period. (Baseline will be 8,000 shares.)

          l5% - Upon confirmation of corporate research coverage from Two (2)
                buy- or sell-side analysts or an endorsement by an appropriate
                investment newsletter publication with a subscriber base in
                excess of 3,000. (Vesting to be prorated at 7.5% for each
                research or recommendation event).
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February 7, 2000
Page 9



          20% - Upon confirmation of securing at least a 12.5 P/E ratio for a
                period of at least 45 calendar days.

          10% - Upon confirmation of two (2) positive financial (non-trade
                oriented) media events, such as articles in newspapers or
                financial magazines of recognized standing such as the Barrons,
                Wall Street Journal, Fortune, Forbes, Business Week Magazine,
                Individual Investor magazine, Investors Business Daily or such
                as source as may be mutually agreed upon in the financial and
                investment community or television or radio media coverage on
                well recognized financial, investment or business programs.
                (Vesting to be prorated at 5% for each media event).


The shares underlying the non-forfeitable, non-cancelable warrant/option issued
will be eligible for registration by demand registration rights via a form S-3
registration statement or by non-proratable piggy-back registration rights
should the Company file an applicable registration. RCG agrees to pay 50% up to
$5,000 in costs associated with such registration. Such payment by RCG is due
upon the effective date of the registration statement. In the event that RCG
provides a written request to exercise any portion or all of its option position
the Company hereby agrees to immediately effectuate such exercise and to file
such registration statement within 15 days of the request.

In the event that AZZ is merged into or a controlling interest is acquired by
any entity, which results in a material change in AZZ management, RCG will be
immediately vested in all remaining options, including those, which to that
point have not yet been vested.