EXHIBIT 10.31

                       SECOND REVOCABLE WARRANT AGREEMENT

                            NATURAL GAS SYSTEMS, INC.

      THIS SECOND  REVOCABLE  WARRANT  AGREEMENT (this  "Agreement") is made and
entered into as of  September___,  2005,  between  Natural Gas Systems,  Inc., a
Nevada corporation (the "Company"),  and Prospect Energy Corporation, a Maryland
Corporation ("Holder").  Terms not defined herein shall have the meaning defined
in the Loan Agreement (defined below).

                                 R E C I T A L S

      WHEREAS,  in consideration for entering into the attached Letter Amendment
to the Loan  Agreement,  attached  hereto as EXHIBIT D, the Company  proposes to
issue to Holder a maximum of TWO HUNDRED THOUSAND  (200,000)  revocable warrants
(the "Revocable  Warrants"),  each such Revocable  Warrant  entitling the holder
thereof to purchase,  under certain conditions,  one share of common stock, .001
par value, of the Company (the "Shares" or the "Common Stock"). ; and

      WHEREAS,  the Revocable  Warrants  which are the subject of this Agreement
will be issued by the Company to Holder as additional consideration related to a
Secured Loan Agreement, attached hereto as EXHIBIT B, made by the Company to the
Holder (the "Loan Agreement");

      WHEREAS,  the  Revocable  Warrants  shall be subject to  revocation by the
Company without any further consideration if the Company meets certain financial
tests specified in Section 3 below.

      NOW, THEREFORE, in consideration of the premises and the mutual agreements
herein set forth, the parties hereto agree as follows:

                                A G R E E M E N T

      1.    Revocable  Warrant  Certificates.  The  warrant  certificates  to be
delivered  pursuant to this Agreement  (the  "Revocable  Warrant  Certificates")
shall be in the form set forth in  Exhibit  A,  attached  hereto and made a part
hereof,  with such appropriate  insertions,  omissions,  substitutions and other
variations as are required or permitted by this Revocable Warrant Agreement.

      2.    Right to Exercise Revocable Warrants.  Each Revocable Warrant may be
exercised,  in whole or in part,  from June 15, 2006 until  11:59 P.M.  (Eastern
Standard  Time)  on the  date  that is five  (5)  years  after  the date of this
Agreement  (the  "Expiration  Date").  Each  Revocable  Warrant not exercised or
revoked on or before the Expiration Date shall expire.

      Other than as specified in Section 3 herein,  each Revocable Warrant shall
entitle its holder to purchase  from the Company one share of Common Stock (each
an  "Exercise  Share") at an  exercise  price of One Dollar and Thirty Six Cents
($1.36) per share, subject to adjustment as set forth below ("Exercise Price").

      The Company  shall not be required  to issue  fractional  shares of Common
Stock upon the  exercise  of this  Revocable  Warrant  or to  deliver  Revocable
Warrant  Certificates which evidence  fractional shares of capital stock. In the
event that a fraction of an Exercise  Share would,  except for the provisions of
this paragraph 2, be issuable upon the exercise of this Revocable  Warrant,  the
Company shall pay to the Holder  exercising  the Revocable  Warrant an amount in
cash  equal to such  fraction  multiplied  by the  current  market  value of the
Exercise Share. For purposes of this paragraph 2, the current market value shall
be determined as follows:


<PAGE>

            (a)   if the Shares are  traded in the  over-the-counter  market and
not on any national  securities exchange and not in the NASDAQ Reporting System,
the  average of the mean  between  the last bid and asked  prices per share,  as
reported by the National  Quotation  Bureau,  Inc., or an  equivalent  generally
accepted reporting service, for the last business day prior to the date on which
the Revocable Warrant is exercised,  or, if not so reported,  the average of the
closing  bid and asked  prices for a Share as  furnished  to the  Company by any
member of the National Association of Securities Dealers,  Inc., selected by the
Company and Holder for that purpose.

            (b)   if the Shares  are  listed or traded on a national  securities
exchange or in the NASDAQ Reporting  System,  the closing price on the principal
national  securities  exchange  on which  they are so listed or traded or in the
NASDAQ Reporting  System,  as the case may be, on the last business day prior to
the date of the exercise of the Revocable Warrant. The closing price referred to
in this  Clause (b) shall be the last  reported  sales price or, in case no such
reported  sale takes place on such day, the average of the reported  closing bid
and asked prices on such day, in either case on the national securities exchange
on which the Shares are then listed or in the NASDAQ Reporting System; or

            (c)   if no such  closing  price or closing bid and asked prices are
available,  as  determined  by the  Holder  and the  Board of  Directors  of the
Company.

      3.    Revocation of the Revocable  Warrants.  Notwithstanding  anything to
the contrary,  all Revocable Warrants granted by the Company to the Holder under
this  Agreement  shall be subject to  forfeiture,  revocation  and  cancellation
without any  further or  additional  consideration  due or owed to Holder in the
event that the Company and its Subsidiaries,  on a consolidated  basis, prior to
May 1, 2006 meets the  "EBITDA  Test," as defined  below in this  Section 3. The
"EBITDA  Test"  shall  mean  that  the  Company  and  its  Subsidiaries,   on  a
consolidated  basis,  generates  EBITDA of at least  $200,000.00  for any single
calendar  month,  calculated  anytime prior to prior to June 1, 2006.  Terms not
defined in this Agreement with regards to this Section 3 are defined in the Loan
Agreement, attached hereto as EXHIBIT B.

      4.    Mutilated or Missing Revocable Warrant Certificates.  In case any of
the Revocable Warrant Certificates shall be mutilated, lost, stolen or destroyed
prior to the Expiration  Date, the Company shall issue and deliver,  in exchange
and substitution for and upon  cancellation of the mutilated  Revocable  Warrant
Certificate,  or in  lieu  of and in  substitution  for  the  Revocable  Warrant
Certificate  lost, stolen or destroyed,  a new Revocable Warrant  Certificate of
like tenor and representing an equivalent right or interest.

      5.    Reservation  of Shares.  The Company  will at all times  reserve and
keep  available,  free  from  preemptive  rights,  out of the  aggregate  of its
authorized  but unissued  Shares or its authorized and issued Shares held in its
treasury  for the  purpose of enabling  it to satisfy  its  obligation  to issue
Exercise Shares upon exercise of Revocable Warrants, the full number of Exercise
Shares deliverable upon the exercise of all outstanding Revocable Warrants.

      The Company  covenants  that all Exercise  Shares which may be issued upon
exercise  of  Revocable  Warrants  will  be  validly  issued,   fully  paid  and
non-assessable outstanding Shares of the Company.

      6.    Rights of  Holder.  The  Holder  shall  not,  by virtue of  anything
contained in this Revocable Warrant Agreement or otherwise, prior to exercise of
this Revocable  Warrant,  be entitled to any right whatsoever,  either in law or
equity, of a stockholder of the Company, including without limitation, the right


                                       2
<PAGE>

to  receive  dividends  or to vote  or to  consent  or to  receive  notice  as a
stockholder  in respect of the  meetings  of  stockholders  or the  election  of
directors of the Company of any other matter.

      7.    Investment  Intent;   Accredited  Investor.  Holder  represents  and
warrants to the Company  that Holder is  acquiring  the  Revocable  Warrants for
investment  purposes and with no present  intention of distributing or reselling
any of the  Revocable  Warrants.  Holder  represents  that it is an  "accredited
investor"  within the meaning of Rule 501 of  Regulation D under the  Securities
Act of 1933, as amended (the "Act").

      8.    Certificates  to  Bear  Legend.   The  Revocable  Warrants  and  the
certificate or certificates  therefore shall bear the following  legend by which
each holder shall be bound:

      "THE  SECURITIES  REPRESENTED BY THIS  INSTRUMENT HAVE NOT BEEN REGISTERED
      UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED
      OR OTHERWISE  TRANSFERRED WITHOUT AN EFFECTIVE  REGISTRATION THEREOF UNDER
      SUCH ACT OR  PURSUANT  TO RULE 144 OR AN  OPINION OF  COUNSEL,  REASONABLY
      SATISFACTORY TO THE CORPORATION AND ITS COUNSEL, THAT SUCH REGISTRATION IS
      NOT REQUIRED."

            The Exercise Shares and the  certificate or certificates  evidencing
any such Exercise Shares shall bear the following legend:

      "THE SECURITIES  REPRESENTED BY THIS  CERTIFICATE HAVE NOT BEEN REGISTERED
      UNDER  THE  SECURITIES  ACT  OF  1933.  THE  SHARES  MAY  NOT BE  SOLD  OR
      TRANSFERRED IN THE ABSENCE OF SUCH  REGISTRATION  OR AN OPINION OF COUNSEL
      ACCEPTABLE TO THE COMPANY THAT AN EXEMPTION FROM  REGISTRATION  UNDER SUCH
      ACT IS AVAILABLE."

      Certificates for Revocable  Warrants or Exercise  Shares,  as the case may
be, without such legend shall be issued if such  Revocable  Warrants or Exercise
Shares are sold pursuant to an effective registration statement under the Act or
if the Company has received an opinion from counsel  reasonably  satisfactory to
counsel for the Company that such legend is no longer required under the Act.

      9.    Adjustment   of  Number  of  Shares  and  Class  of  Capital   Stock
Purchasable.   The  number  of  Exercise  Shares  and  class  of  capital  stock
purchasable  under this Revocable Warrant are subject to adjustment from time to
time as set forth in this Section 9.

            (a)   Adjustment for Change in Capital Stock. If the Company:

                  (i)   pays a dividend  or makes a  distribution  on its Common
                        Stock, in each case, in shares of its Common Stock;

                  (ii)  subdivides its outstanding shares of Common Stock into a
                        greater number of shares;

                  (iii) combines its  outstanding  shares of Common Stock into a
                        smaller number of shares; or

                  (iv)  makes a  distribution  on its Common  Stock in shares of
                        its capital stock other than Common Stock


                                       3
<PAGE>

then the number and classes of Exercise Shares purchasable upon exercise of each
Revocable  Warrant in effect  immediately prior to such action shall be adjusted
so that the holder of any Revocable Warrant thereafter exercised may receive the
number and classes of shares of capital  stock of the Company  which such holder
would have owned immediately  following such action if such holder had exercised
the Revocable Warrant immediately prior to such action.

      For a dividend or  distribution  the  adjustment  shall  become  effective
immediately  after the  record  date for the  dividend  or  distribution.  For a
subdivision,  combination  or  reclassification,  the  adjustment  shall  become
effective  immediately after the effective date of the subdivision,  combination
or reclassification.

      If after an adjustment the holder of a Revocable  Warrant upon exercise of
it may receive  shares of two or more  classes of capital  stock of the Company,
the  Board of  Directors  of the  Company  shall  in good  faith  determine  the
allocation  of the  adjusted  Exercise  Price  between  or among the  classes of
capital  stock.  After  such  allocation,  that  portion of the  Exercise  Price
applicable to each share of each such class of capital stock shall thereafter be
subject to  adjustment on terms  comparable to those  applicable to the Exercise
Shares in this Agreement.

            (b)   Consolidation,  Merger or Sale of the Company.  If the Company
is a party to a consolidation,  merger, transfer of assets or any other business
combination  which  reclassifies  or changes its outstanding  Common Stock,  the
successor  corporation (or corporation  controlling the successor corporation or
the Company,  as the case may be) shall by operation of law assume the Company's
obligations under this Agreement.  Upon  consummation of such  transaction,  the
Revocable  Warrants  shall  automatically  become  exercisable  for the kind and
amount of  securities,  cash or other  assets  which the  holder of a  Revocable
Warrant would have owned immediately after the consolidation,  merger,  transfer
or  business  combination  if the holder had  exercised  the  Revocable  Warrant
immediately before the effective date of such transaction. As a condition to the
consummation  of such  transaction,  the Company shall arrange for the person or
entity  obligated  to issue  securities  or deliver  cash or other  assets  upon
exercise of the Revocable Warrant to, concurrently with the consummation of such
transaction,   assume  the  Company's  obligations  hereunder  by  executing  an
instrument so providing and further  providing for adjustments which shall be as
nearly  equivalent as may be practical to the  adjustments  provided for in this
Section  9.  The  provisions  of this  Section  9(b)  shall  similarly  apply to
successive reclassifications,  reorganizations, consolidations, mergers or other
business combinations.

      10.   Successors. All the covenants and provisions of this Agreement by or
for the benefit of the Company or Holder  shall bind and inure to the benefit of
their respective successor and assigns hereunder.

      11.   Counterparts.  This  Agreement  may be  executed  in any  number  of
counterparts and each of such  counterparts  shall for all proposes be deemed to
be an original,  and such counterparts shall together  constitute by one and the
same instrument.

      12.   Notices.  All notices or other  communications  under this Agreement
shall be in writing and shall be deemed to have been given if  delivered by hand
or  mailed  by  certified  mail,  postage  prepaid,  return  receipt  requested,
addressed as follows: if to the Company: Natural Gas Systems, Inc., Two Memorial
City Plaza,  820  Gessner,  Suite 1340.  Houston,  TX 77024 ,  Attention:  Chief
Executive Officer,  and to the Holder: at the address of the Holder appearing on
the books of the Company or the Company's transfer agent, if any.


                                       4
<PAGE>

      Either the  Company or the Holder may from time to time change the address
to which notices to it are to be mailed  hereunder by notice in accordance  with
the provisions of this Paragraph 12.

      13.   Supplements  and  Amendments.  The  Company  may  from  time to time
supplement or amend this Agreement  without the approval of any Holders in order
to cure any  ambiguity or to be correct or supplement  any  provision  contained
herein which may be defective or inconsistent  with any other  provision,  or to
make any other  provisions  in regard to matters  or  questions  herein  arising
hereunder  which the Company may deem necessary or desirable and which shall not
materially  adversely affect the interest of the Holder.  Except as set forth in
the immediately  preceding  sentence,  this Agreement may not be amended without
the prior written consent of the Holder.

      14.   Severability. If for any reason any provision,  paragraph or term of
this  Agreement  is  held  to be  invalid  or  unenforceable,  all  other  valid
provisions  herein  shall  remain  in full  force  and  effect  and  all  terms,
provisions and paragraphs of this Agreement shall be deemed to be severable.

      15.   Governing Law. This Agreement  shall be deemed to be a contract made
under the laws of the State of Nevada and for all purposes shall be governed and
construed in accordance with the laws of said State.

      16.   Headings.  Paragraphs  and  subparagraph  headings,  used herein are
included  herein  for  convenience  of  reference  only and shall not affect the
construction  of this  Agreement nor constitute a part of this Agreement for any
other purpose.

      IN WITNESS  WHEREOF,  the parties  hereto have caused this Agreement to be
duly executed, as of the date and year first above written.

COMPANY                                        HOLDER:
NATURAL GAS SYSTEMS, INC.                      PROSPECT ENERGY CORPORATION


By:_______________________________             By:______________________________
Name: Robert S. Herlin, CEO                    Name:____________________________


                                       5
<PAGE>

                                    EXHIBIT A


THE SECURITIES REPRESENTED BY THIS INSTRUMENT HAVE NOT BEEN REGISTERED UNDER THE
SECURITIES  ACT OF 1933, AS AMENDED,  AND MAY NOT BE SOLD,  PLEDGED OR OTHERWISE
TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT OR PURSUANT
TO RULE 144 OR AN OPINION OF COUNSEL, REASONABLY SATISFACTORY TO THE CORPORATION
AND ITS COUNSEL, THAT SUCH REGISTRATION IS NOT REQUIRED.

                   SECOND REVOCABLE WARRANT TO PURCHASE SHARES
                   OF COMMON STOCK OF NATURAL GAS SYSTEMS, INC


Initial Number of Shares:         200,000
Exercise Price:                   $1.36 per share
Date of Grant:                    September ___, 2005
Expiration Date:                  September ___, 2010

THIS CERTIFIES THAT, Prospect Energy Corporation, a Maryland corporation, or any
person or entity to whom the  interest  in this  Revocable  Warrant is  lawfully
transferred  ("Holder")  is entitled to purchase  the above  number (as adjusted
pursuant  to Section 4 hereof) of fully  paid and  non-assessable  shares of the
Common Stock (the "Shares") of Natural Gas Systems,  Inc., a Nevada  corporation
(the  "Company),  having an Exercise  Price as set forth  above,  subject to the
provisions  and upon the  terms  and  conditions  set  forth  herein  and in the
Revocable  Warrant  Agreement  dated  September  __,  2005  ("Revocable  Warrant
Agreement").  The  exercise  price,  as  adjusted  from time to time as provided
herein, is referred to as the "Exercise Price."

NOTWITHSTANDING  ANYTING TO THE CONTRARY,  THIS REVOCABLE  WARRANT IS SUBJECT TO
REVOCATION WITHOUT CONSIDERATION BY THE COMPANY UNDER CERTAIN CONDITIONS DEFINED
IN THE REVOCABLE WARRANT AGREEMENT.

      1.    Term.  Subject  to the  revocation  provisions  of  Section 3 of the
Revocable  Warrant  Agreement,  the purchase right represented by this Revocable
Warrant is exercisable,  in whole or in part, at any time commencing on the June
15,  2006 and ending on the  Expiration  Date,  after  which time the  Revocable
Warrant shall be void.

      2.    Method of  Exercise;  Payment;  Issuance of New  Revocable  Warrant.
Subject to Section 1 hereof,  the right to purchase  Shares  represented by this
Revocable Warrant may be exercised by Holder, in whole or in part, for the total
number of Shares  remaining  available  for  exercise by the  surrender  of this
Revocable Warrant (with the notice of exercise form attached hereto as Exhibit A
duly executed) at the principal  office of the Company and by the payment to the
Company,  by check made payable to the Company drawn on a United States bank and
for  United  States  funds,  or by  delivery  to  the  Company  of  evidence  of
cancellation of  indebtedness of the Company to such Holder,  of an amount equal
to the then  applicable  Exercise  Price per share  multiplied  by the number of
Shares then being purchased or by net exercise  pursuant to Section 6 hereof. In
the event of any exercise of the purchase  right  represented  by this Revocable
Warrant, certificates for the Shares so purchased shall be promptly delivered to
Holder  and,  unless this  Revocable  Warrant  has been fully  exercised  or has
expired, a new Revocable Warrant representing the portion of the Shares, if any,
with respect to which this Revocable  Warrant shall not then have been exercised
shall also be promptly delivered to Holder.


<PAGE>

      3.    Exercise Price.  The Exercise Price at which this Revocable  Warrant
may be exercised  shall be the  Exercise  Price,  as adjusted  from time to time
pursuant to Section 4 hereof.

      4.    Adjustment of Number of Shares. The number of shares and/or class of
capital stock purchasable upon exercise of this Revocable Warrant are subject to
adjustment as provided in Section 9 of the Revocable Warrant Agreement.

      5.    Transferability   and  Negotiability  of  Revocable  Warrant.   This
Revocable Warrant may not be transferred or assigned in whole or in part without
compliance with applicable  federal and state  securities laws by the transferor
and the transferee  (including,  without limitation,  the delivery of investment
representation  letters  and  legal  opinions  reasonably  satisfactory  to  the
Company, if reasonably  requested by the Company).  Subject to the provisions of
this Section 5, title to this  Revocable  Warrant may be transferred in the same
manner as a negotiable instrument transferable by endorsement and delivery.

      6.    Net Exercise. In lieu of exercising this Revocable Warrant for cash,
the Holder may elect to exchange this Revocable  Warrant for Shares equal to the
value of this Revocable Warrant by surrender of this Revocable Warrant, together
with notice of such election,  at the principal office of the Company,  in which
event the Company  shall issue to the holder a number of Shares  computed  using
the following formula:

                                                     X = Y (A-B)
                                                         -------
                                                            A
         Where:

            X= the number of Shares to be issued to the holder.
            Y= the  number  of  Shares  to be  purchased  under  this  Revocable
               Warrant.
            A= value  per  share of one  Share  determined  in  accordance  with
               Section 2 of the Revocable Warrant Agreement.
            B= the Exercise Price (as adjusted).

      7.    Registration  Rights.  Upon exercise of this Revocable Warrant , the
Holder shall have and be entitled to exercise,  together  with all other holders
of registrable securities possessing "piggy back" registration rights under that
certain Registration Rights Agreement, of even date herewith and attached hereto
as  EXHIBIT C,  between  the  Company  and the  parties  who have  executed  the
counterpart  signature  pages  thereto  or  are  otherwise  bound  thereby  (the
"Registration  Rights Agreement"),  the rights of registration granted under the
Registration  Rights  Agreement  (with  respect  to the  Shares of Common  Stock
issuable  upon  exercise  of this  Revocable  Warrant ). By its  receipt of this
Revocable  Warrant  ,  Holder  agrees  to be  bound by the  Registration  Rights
Agreement.

      8.    Miscellaneous.  The  Company  covenants  that it  will at all  times
reserve and keep  available,  solely for the purpose of issue upon the  exercise
hereof,  a sufficient  number of Shares to permit the  exercise  hereof in full.
Such Shares,  when issued in compliance  with the  provisions of this  Revocable
Warrant and the Company's Certificate of Incorporation, will be duly authorized,
validly  issued,  fully  paid and  non-assessable.  No Holder of this  Revocable
Warrant,  as such, shall,  prior to the exercise of this Revocable  Warrant,  be
entitled to vote or receive  dividends or be deemed to be a  stockholder  of the
Company for any purpose,  nor shall anything contained in this Revocable Warrant
be construed to confer upon Holder,  as such, any rights of a stockholder of the
Company or any right to vote, give or withhold consent to any corporate  action,
receive  notice of  meetings,  receive  dividends  or  subscription  rights,  or
otherwise.  Upon receipt of evidence  reasonably  satisfactory to the Company of
the loss, theft, destruction or mutilation of this Revocable Warrant and, in the
case of any such loss,  theft or  destruction,  upon  delivery  of an  indemnity


                                       2
<PAGE>

agreement  reasonably  satisfactory in form and amount to the Company or, in the
case of any such  mutilation,  upon surrender and cancellation of such Revocable
Warrant, the Company at its expense will execute and deliver, in lieu thereof, a
new Revocable  Warrant of like date and tenor.  The terms and provisions of this
Revocable  Warrant  shall  inure to the  benefit  of, and be binding  upon,  the
Company and the Holder hereof and their respective  successors and assigns. This
Revocable Warrant shall be governed by and construed under the laws of the State
of Nevada.


                                       3
<PAGE>

      IN WITNESS WHEREOF, the parties have executed and delivered this Agreement
as of the date and year first written above.

Holder:                                Company:
________________________________       Natural Gas Systems, a Nevada Corporation


By:_____________________________       By:____________________________________

Name:___________________________       Name:__________________________________


                                       4
<PAGE>

                               NOTICE OF EXERCISE

TO:   NATURAL GAS SYSTEMS, INC.


      1.    The undersigned  hereby elects to purchase  _________  shares of the
Common Stock of NATURAL GAS SYSTEMS,  INC. pursuant to the terms of the attached
Revocable  Warrant,  and tenders  herewith payment of the purchase price of such
shares in full, together with all applicable transfer taxes, if any.

      2.    The undersigned  hereby elects to purchase  __________ shares of the
Common Stock of NATURAL GAS SYSTEMS,  INC. pursuant to the terms of the attached
Revocable Warrant on a net exercise basis in accordance with Section 6.

      3.    Please issue a certificate or certificates  representing said shares
of the Common Stock in the name of the  undersigned  or in such other name as is
specified below:




                                        Name:___________________________________

                                        Tax ID:___________________


                                        Address:________________________________

                                                ________________________________

                                                ________________________________

                                                ________________________________

                                                ________________________________



                                        Signed:_________________________________



                                        Date:___________________


                                       5