Document:

<PAGE>
                                                                 Exhibit 10 (mm)
                             STATE OF SOUTH DAKOTA
                         BOARD OF ECONOMIC DEVELOPMENT

               REVOLVING ECONOMIC DEVELOPMENT AND INITIATIVE FUND
                                 (ARSD 68:02:01)

                              EMPLOYMENT AGREEMENT

                                                        REDI LOAN NUMBER 02-18-A

         EMPLOYMENT AGREEMENT, made and entered into this 19th day of December,
2002, by and between the State of South Dakota, Board of Economic Development,
711 Wells Avenue, Pierre, South Dakota 57501 (herein "BED"), and M-tron
Industries, Inc., of 100 Douglas Avenue, Yankton, South Dakota 57078 (herein the
"Borrower").

         WHEREAS, M-tron Industries, Inc., (the "Borrower") made an application
(the "Application") dated September 20, 2002, to BED for a loan from the
Revolving Economic Development and Initiative Fund (REDI), for the purposes of
Borrower's business expansion or relocation in the State of South Dakota (the
"Project"), as described with particularity in the Application and the BED Loan
Documents, which are by this reference incorporated herein; and,

         WHEREAS, the Application was approved by BED and the Borrower and BED
entered into a certain Revolving Economic Development and Initiative Fund (REDI)
Loan Agreement dated the 19th day of December, 2002, (the "Loan Agreement"),
whereby BED loaned to Borrower from the REDI Fund the sum of $296,000, together
with interest thereon at 3% per annum, due and payable as set forth in the
Promissory Note of even date, all pursuant to SDCL Chapter 1-33 and 1-16G, as
amended, and ARSD Article 68:02 (the"BED Loan"); and,

         WHEREAS, the BED Loan accrues interest at the rate of three percent per
annum, which interest rate is below the prevailing rate available from
commercial lending institutions at the time the BED Loan was made; and,

         WHEREAS, part of the inducement and consideration for BED to make said
BED Loan to Borrower is the Project's creation of employment opportunities for
South Dakota citizens, as set forth in the projections made by Borrower in the
Application; and,

         WHEREAS, failure of Borrower to meet the projections in the Application
will constitute a failure of consideration, and a default under the terms and
conditions of this Employment Agreement, the Loan Agreement, Promissory Note,
and other Loan Documents executed by Borrower and BED in connection with this
Application, BED Loan, and Project, all of which documents are incorporated by
reference herein;

                                   Page 1 of 3

<PAGE>

         NOW, THEREFORE IT IS MUTUALLY AGREED AS FOLLOWS:

         1. The parties specifically agree that due to the nature of the
consideration for the BED Loan to the Borrower it is impracticable or extremely
difficult to fix the actual damages resulting from the breach of this Employment
Agreement, the Loan Agreement, the Promissory Note, or the other Loan Documents.

         2. The parties specifically agree that it will constitute an event of
default under the terms and conditions of this Employment Agreement and the Loan
Agreement if the Borrower fails to meet the employment projections set forth in
the Application, or substantially changes the nature of the Project or ceases
operations or relocates the business or Project from Yankton, South Dakota, so
that there is a loss of the employment created by the Project in that area of
the State, within five years from the date of this Employment Agreement or the
term of the BED Loan whichever is longer. In the event of a default, then the
total indebtedness owed by the Borrower to the BED, including principal and
interest, and the payment of liquidated damages by the Borrower to BED, shall at
the option of BED immediately become due and payable upon twenty (20) days'
written notice to the Borrower. It is agreed that liquidated damages will be
computed as follows:

         Damages shall be an amount equal to the difference between the total
         interest paid on each payment date prior to the final payment of the
         BED Loan and on the final payment date (whether at maturity or upon
         prepayment) and the total interest that would have been paid on those
         dates had the BED Loan been made at 5.25%, the current commercial rate
         at the time of this Employment Agreement, rather than 3%, the interest
         rate at which BED made the BED Loan to Borrower. If BED demands such
         liquidated damages five years or more after the date of the Loan
         Agreement, and each monthly installment payment and the final payment
         on the BED Loan shall have been made when due without prepayment, and
         if no default exists, then the damages due and owing to BED will be
         $21,180.

         3. This Employment Agreement is made in consideration of the BED Loan.

         4. This Employment Agreement shall be governed by and construed in
accordance with the laws of the State of South Dakota. Any lawsuit pertaining to
or affecting this Employment Agreement shall be venued in Circuit Court, Sixth
Judicial Circuit, Hughes County, South Dakota.

         5. This Employment Agreement may not be modified or amended except by
mutual consent expressed in writing, which writing shall be expressly identified
as a part hereof, and which writing shall be signed by an authorized
representative of each of the parties hereto.

         6. Any notice provided for herein shall be deemed given when
transmitted as provided in Section 14 of the Loan Agreement.

                                   Page 2 of 3

<PAGE>

         7. The covenants in this Employment Agreement shall be deemed to be
severable; in the event that any portion of this Employment Agreement is
determined to be void or unenforceable, that determination shall not affect the
validity of the remaining portions of the Employment Agreement.

         8. Terms used herein and defined in the Loan Agreement shall have the
same meaning as set forth in the Loan Agreement unless the context clearly
requires otherwise.

         9. Time is of the essence in the performance of the covenants, terms
and conditions contained in this Employment Agreement. This Employment Agreement
shall be binding upon and inure to the benefit of the parties hereto and their
respective transferees, successors and assigns except that the Borrower may not
assign or transfer it rights under the Loan Documents without prior written
consent of BED

         Dated this 19th day of December, 2002.

                                                 SOUTH DAKOTA BOARD OF
                                                 ECONOMIC DEVELOPMENT

                                                 BY:  /s/ Anthony Klein
                                                      --------------------------
 (SEAL)
                                                 ITS: TREASURER

                                                 M-TRON INDUSTRIES, INC.

 (SEAL)                                          BY:  /s/ Robert R. Zylstra
                                                      ---------------------
                                                 ITS: President & CEO

ATTEST:

BY:  David L. Rein
     -----------------------
ITS: Secretary

NOTE: Corporate Borrowers must execute Employment Agreement, in corporate name,
by duly authorized officer, and seal must be affixed and duly attested.

                                  Page 3 of 3<PAGE>

                                                                     Exhibit 4.1

     NUMBER                                                         UNITS
U-__________

  SEE REVERSE FOR         TREMISIS ENERGY ACQUISITION CORPORATION
CERTAIN DEFINITIONS

                                                                CUSIP 894727205

         UNITS CONSISTING OF ONE SHARE OF COMMON STOCK AND TWO WARRANTS
                   EACH TO PURCHASE ONE SHARE OF COMMON STOCK

THIS CERTIFIES THAT
                   -------------------------------------------------------------
is the owner of                                                           Units.
                ---------------------------------------------------------

Each Unit ("Unit") consists of one (1) share of common stock, par value $.0001
per share ("Common Stock"), of Tremisis Energy Acquisition Corporation, a
Delaware corporation (the "Company"), and two warrants (the "Warrants"). Each
Warrant entitles the holder to purchase one (1) share of Common Stock for $5.00
per share (subject to adjustment). Each Warrant will become exercisable on the
later of (i) the Company's completion of a merger, capital stock exchange, asset
acquisition or other similar business combination or (ii) ______________, 2005
and will expire unless exercised before 5:00 p.m., New York City Time, on
____________, 2008, or earlier upon redemption (the "Expiration Date"). The
Common Stock and Warrants comprising the Units represented by this certificate
are not transferable separately prior to __________, 2004, subject to earlier
separation in the discretion of EarlyBirdCapital, Inc. The terms of the Warrants
are governed by a Warrant Agreement, dated as of _______, 2004, between the
Company and Continental Stock Transfer & Trust Company, as Warrant Agent, and
are subject to the terms and provisions contained therein, all of which terms
and provisions the holder of this certificate consents to by acceptance hereof.
Copies of the Warrant Agreement are on file at the office of the Warrant Agent
at 17 Battery Place, New York, New York 10004, and are available to any Warrant
holder on written request and without cost.

    This certificate is not valid unless countersigned by the Transfer Agent and
Registrar of the Company.

    Witness the facsimile seal of the Company and the facsimile signature of its
duly authorized officers.

By

                                        [SEAL]
-------------------------------------              -----------------------------
                Chairman of the Board              Secretary

<PAGE>

                     TREMISIS ENERGY ACQUISITION CORPORATION

         The Company will furnish without charge to each stockholder who so
requests, a statement of the powers, designations, preferences and relative,
participating, optional or other special rights of each class of stock or series
thereof of the Company and the qualifications, limitations, or restrictions of
such preferences and/or rights.

         The following abbreviations, when used in the inscription on the face
of this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

<TABLE>
<S>                 <C>                                           <C>
         TEN COM -  as tenants in common                          UNIF GIFT MIN ACT - ______ Custodian _______
         TEN ENT -  as tenants by the entireties                                      (Cust)          (Minor)
         JT TEN -   as joint tenants with right of survivorship                 under Uniform Gifts to Minors
                    and not as tenants in common                                Act ______________
                                                                                        (State)
</TABLE>

Additional Abbreviations may also be used though not in the above list.

         For value received, ___________________________ hereby sell, assign and
transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
    IDENTIFYING NUMBER OF ASSIGNEE

----------------------------------------

----------------------------------------

--------------------------------------------------------------------------------
 (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING ZIP CODE, OF ASSIGNEE)

--------------------------------------------------------------------------------

--------------------------------------------------------------------------------

                                                                        Units
-----------------------------------------------------------------------

represented by the within Certificate, and do hereby irrevocably constitute and

appoint                                                               Attorney
        -------------------------------------------------------------

to transfer the said Units on the books of the within named Company will full
power of substitution in the premises.

Dated
      ---------------                 ------------------------------------------
                                      NOTICE:  The signature to this assignment
                                               must correspond with the name as
                                               written upon the face of the
                                               certificate in every particular,
                                               without alteration or enlargement
                                               or any change whatever.

Signature(s) Guaranteed:

--------------------------------------------------------------------------------
THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION
(BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH
MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM, PURSUANT TO
S.E.C. RULE 17Ad-15).

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00064-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00064-of-00352.parquet"}]]