PROMISSORY NOTE
                                 ---------------


Date:    December 2, 2005

Maker:   HEMIWEDGE VALVE CORPORATION, a Texas corporation

Maker's Mailing Address:

         12060 FM 3083
         Conroe, TX  77301


Payee:   SODERBERG RESEARCH AND DEVELOPMENT, INC.,
         a Texas corporation
         INPROP, INC. , a Texas corporation
         JEANNETTE SODERBERG, an individual

Payee's Mailing Address:

         176 April Cove
         Montgomery, TX  77356

Place for Payment (including county):

         600 Travis, 53rd Floor
         Houston, Texas  77002

Principal Amount:

         ONE HUNDRED THOUSAND and NO/100 DOLLARS ($100,000.00).

Annual Interest Rate on Unpaid Principal Amount:

         Interest at the rate of Six Percent (6%) per month for 24 months.

Annual Interest Rate on Past Due Amounts:

         Past due  principal  and interest  shall bear interest from the date
         due until paid at a default rate of Twelve Percent (12%) per annum.



                                 Promissory Note
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Terms of Payment (principal and interest):

              Unpaid principal and accrued interest thereon, together with
              all other  sums due  hereunder,  shall be  payable as herein
              provided in  twenty-four  equal  installments,  beginning on
              January 1, 2006 and ending on December 1, 2007.

         For  Value  received,  Maker  promises  to pay to the order of Payee in
lawful  money of the  United  States  at the Place for  Payment  (or such  other
address as the Payee may  designate  to the Maker in writing  from time to time)
and according to the Terms of Payment,  the Principal Amount, or so much thereof
as shall have been advanced hereunder from time to time and remain unpaid,  plus
interest as  provided  herein at the rate stated  above.  Interest,  as provided
herein, shall be computed on the basis of the actual number of days elapsed over
a 365-day or, if applicable, 366-day year.

         If Maker  defaults  in the timely  payment of this note and the default
continues  after ninety (90) days' prior  written  notice  thereof from Payee to
Maker, then Payee may at its option declare the outstanding  principal amount of
this note and all  accrued  interest  thereon  immediately  due.  Maker and each
surety, endorser and guarantor waive all demands for payment,  presentations for
payment, notices of intention to accelerate maturity,  notice of acceleration of
maturity, protests and notices of protest.

         If this  note is given to an  attorney  for  collection,  or if suit is
brought for collection,  or if it is collected through probate,  bankruptcy,  or
other judicial  proceeding,  then Maker shall pay Payee all reasonable  costs of
collection, including reasonable attorneys' fees and court costs, in addition to
all other amounts due.

         Notwithstanding  any  other  provision  hereof,  interest  on the  debt
evidenced  by this note  shall not  exceed  the  maximum  amount of  nonusurious
interest that may be contracted for,  charged or received under  applicable law;
any interest in excess of that maximum amount shall be credited on the principal
of the debt or, if that has been paid, refunded. On any acceleration or required
or permitted prepayment,  any such excess shall be canceled  automatically as of
the acceleration or prepayment or, if already paid, credited on the principal of
the debt  or,  if the  principal  of the debt  has  been  paid,  refunded.  This
provision  overrides  all other  provisions  in this and all  other  instruments
concerning the debt evidenced by this note.

         Maker may from  time to time  prepay  all or part of this note  without
penalty  and  interest  shall  cease to accrue on the  portion of the  Principal
Amount prepaid as of the date of prepayment.  Prepayments shall be applied first
to accrued unpaid interest and then to principal.



                                 Promissory Note
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         This note may be amended  only by the  written  agreement  of Maker and
Payee  and any  right  or power of Payee  hereunder  may be  waived  only by the
written agreement of Payee. Delay by Payee in the exercise of any right or power
hereunder  shall not operate as a waiver of such right or power and no waiver by
Payee  of any  right  or  power  hereunder  shall  operate  as a  waiver  of any
subsequent  right or power unless  specifically  provided to the contrary in the
written agreement evidencing such waiver.

         The rights and obligations evidenced by this note shall be binding upon
and inure to the benefit of Maker and Payee and their  respective  heirs,  legal
representatives,  successors and assigns; provided,  however, that no assignment
or other  transfer of this note by Maker shall relieve Maker of its  obligations
to Payee hereunder in the absence of the prior written agreement of Payee.

         THIS NOTE HAS BEEN  EXECUTED AND DELIVERED IN THE STATE OF TEXAS AND IT
SHALL BE ENFORCED AND CONSTRUED IN ACCORDANCE WITH THE SUBSTANTIVE LAWS THEREOF.

         Each  Maker,  if more  than one,  is  responsible  for all  obligations
represented by this note.

         When the context  requires,  singular  nouns and pronouns shall include
the plural,  the masculine shall include the feminine  gender (and  vice-versa),
and the term Payee shall include the successors and assigns thereof.


         THIS NOTE EMBODIES THE ENTIRE AGREEMENT AND UNDERSTANDING BETWEEN PAYEE
AND MAKER AND OTHER PARTIES WITH RESPECT TO THEIR  SUBJECT  MATTER AND SUPERSEDE
ALL PRIOR CONFLICTING OR INCONSISTENT  AGREEMENTS,  CONSENTS AND  UNDERSTANDINGS
RELATING TO SUCH SUBJECT MATTER.  MAKER ACKNOWLEDGES AND AGREES THAT THERE IS NO
ORAL AGREEMENT  BETWEEN MAKER AND PAYEE WHICH HAS NOT BEEN  INCORPORATED IN THIS
NOTE.


                                 HEMIWEDGE VALVE CORPORATION,
                                 a Texas corporation

                                 By: /s/ Larry C. Shumate
                                     -----------------------------------
                                     Larry C. Shumate
                                     President



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                                 Promissory Note
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