EXHIBIT 10.4

THE INTERESTS SUBSCRIBED FOR BY THIS AGREEMENT HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY APPLICABLE STATE SECURITIES LAWS,
AND TRANSFER OF THE INTERESTS IS RESTRICTED BY THE TERMS OF THIS AGREEMENT AND
OF THE PARTNERSHIP AGREEMENT AND BY APPLICABLE LAW.

                             SUBSCRIPTION AGREEMENT

To:      PHT STENT PARTNERS, L.P.

Gentlemen:

1. Subscription. The undersigned hereby subscribes for and agrees to purchase
Limited Partnership Interests ("Interests") in PHT Stent Partners, LP., a
Delaware limited partnership ("the Partnership"). The number of Interests which
the undersigned hereby subscribes for and agrees to purchase are set forth on
the Signature Page and Power of Attorney attached hereto.

2. Payment.

      (a) At the time of delivery of these completed subscription materials to
the General Partner, a Purchaser must fund 100% of its initial Capital
Contribution (as defined in the Limited Partnership Agreement of the Partnership
(the "Partnership Agreement")) by wire transfer in accordance with the wire
transfer instructions included on the Instructions page.

      (b) The undersigned understands that the amount funded by the undersigned
pursuant to this Paragraph 2 will be held until a closing on the Interests has
occurred. If the General Partner allocates fewer Interests to the Purchaser than
the Purchaser has subscribed for, or rejects the Purchaser's subscription, that
portion of the initial Capital Contribution in excess of the final initial
Capital Contribution will promptly be refunded with interest earned thereon, if
any.

3. Representations, Warranties and Covenants. By executing this Subscription
Agreement, the undersigned further:

      (a) acknowledges that the undersigned has received, carefully read and
understands the Partnership Agreement and all exhibits thereto, and the
Disclosure Materials dated December 11, 2004 (collectively, the "Offering
Materials"), has based a decision to invest on the information contained in the
Offering Materials and has not been furnished with any other offering literature
or prospectus.

      (b) represents and warrants that the undersigned is acquiring the
Interests for the account of the undersigned as principal for investment and not
with a view toward resale or distribution thereof, provided that the Interests
may be resold if registered under the Securities Act of 1933, as amended (the
"Securities Act") or pursuant to an applicable exemption therefrom.


                                       1
<PAGE>

      (c) represents and warrants that the undersigned has, together with the
Purchaser Representative for the undersigned, if any, such knowledge and
experience in financial and business matters that he, she or its is capable of
evaluating the merits and risks of the investment in the Interests.

      (d) represents and warrants that (i) if an individual, the undersigned is
at least twenty-one (21) years of age, (ii) the undersigned maintains his or her
domicile (and is not a transient or temporary resident) at the address shown
below, (iii) if an individual, the undersigned has adequate means of providing
for his or her current needs and personal contingencies, (iv) the undersigned
has no need for liquidity in his investment in the Interests, (v) all of the
undersigned's investments in and commitments to nonliquid investments are, and
after a purchase of the Interests will be, reasonable in relation to the
undersigned's net worth and current needs, (vi) the undersigned is able to bear
the economic risk of losing the entire investment in the Interests, and (vii)
the personal financial information provided by the undersigned accurately
reflects the undersigned's financial condition, with respect to which the
undersigned does not anticipate any material adverse changes.

      (e) understands that the General Partner shall have the right, in its sole
discretion, to accept or reject this subscription, in whole or in part, at any
time prior to closing, or to allocate to the undersigned only part of the
Interests for which the undersigned has subscribed. The General Partner will
notify the undersigned whether this subscription is accepted or rejected. In the
event the subscription is rejected, the undersigned's payment will be returned
with interest earned thereon, if any, and all of the undersigned's obligations
hereunder shall terminate.

      (f) understands that if the undersigned is in default pursuant to the
Partnership Agreement, the undersigned's Interests maybe sold.

      (g) understands that the Interests have not been registered under the
Securities Act, or the securities laws of any state and, as a result thereof,
are subject to substantial restrictions on transfer.

      (h) agrees that the undersigned will not sell or otherwise transfer the
Interests or any interest therein except as permitted pursuant to Article VIII
of the Partnership Agreement.

      (i) understands that (i) the Partnership has no obligation or intention to
register the Interests for resale under any federal or state securities laws, or
to take any action (including the filing of reports or the publication of
information required by Rule 144 under the Securities Act) which would make
available any exemption from the registration requirements of such laws, and
(ii) therefore, the undersigned may be precluded from selling or otherwise
transferring or disposing of the Interests or any portion thereof and may have
to bear the economic risk of investment in the Interests for the term of the
Partnership.

      (j) understands that an investment in the Partnership involves certain
risks and has taken full cognizance of and understands all of the risk factors
relating to the purchase of Interests, including those set forth in the Risk
Factors discussion included in the Disclosure Materials.


                                       2
<PAGE>

      (k) understands that the Offering Materials and other information
furnished by the Partnership and the General Partner do not constitute
investment, accounting, legal or tax advice. The undersigned, in making this
investment, is relying, if at all, solely upon the advice of the undersigned's
personal tax advisers with respect to the federal and/or state tax aspects of an
investment in the Partnership, and neither the Partnership nor the General
Partner has made any representation regarding the tax consequences of investment
in the Interests.

      (1) understands that no federal or state agency has approved or
disapproved the Interests, passed upon or endorsed the merits of the offering
thereof, or made any finding or determination as to the fairness of the
Interests for investment.

      (m) acknowledges that the undersigned has had an opportunity to consult
with counsel and other advisers about an investment in the Interests and that
all material documents, records and books pertaining to this investment have, on
request, been made available to the undersigned and his or her advisers.

      (n) acknowledges that by executing the Signature Page and Power of
Attorney attached hereto, the undersigned is appointing the General Partner (and
any additional or substitute general partner) to be the agent and
attorney-in-fact of the undersigned for certain purposes.

      (o) acknowledges that, if the undersigned is purchasing the Interests
subscribed for hereby in a fiduciary capacity, the representations and
warranties in this Paragraph 3 shall be deemed to have been made on behalf of
the person or persons for whom the undersigned is so purchasing.

      (p) acknowledges that the Partnership has made available to the
undersigned and his or her advisors and Purchaser Representative, if any, the
opportunity to ask questions of, and receive answers from, the Partnership
concerning the terms and conditions of the offering and to obtain any additional
information, to the extent that the Partnership possesses such information, or
can acquire it without unreasonable effort or expense, necessary to verify the
accuracy of the information given to him, her or them or otherwise make an
informed investment decision.

      (q) acknowledges that, if the undersigned has used the services of a
Purchaser Representative in connection with an investment in the Partnership,
such Purchaser Representative has disclosed, by submitting to the undersigned a
Purchaser Representative Letter, in the form given to the undersigned by the
Partnership, any material relationship between such Purchaser Representative or
such Purchaser Representative's affiliates and the Partnership and its
affiliates, which now exists or mutually is understood to be contemplated or
which has existed at any time during the previous two (2) years, and further
setting forth any compensation received or to be received as a result of such
relationship.

      (r) represents and warrants that, except as otherwise disclosed to the
Partnership in writing, the undersigned does not own, directly or indirectly
(within the meaning of the attribution rules set forth in Section 318 of the
Internal Revenue Code of 1986, as amended), any stock or other interests in the
General Partner or any member of its affiliated group, as that term is defined
in Section 1504(a) of the Internal Revenue Code of 1986, as amended.


                                       3
<PAGE>

      (s) understands that the Interests are being offered and sold in reliance
on specific exemptions from the registration requirements of federal and state
securities laws and that the Partnership, the General Partner and controlling
persons thereof are relying upon the truth and accuracy of the representations,
warranties, agreements, acknowledgments and understandings set forth herein in
order to determine the applicability of such exemptions and the suitability of
the undersigned to acquire Interests.

      (t) represents and warrants that the information set forth herein and in
the Confidential Purchaser Questionnaire concerning the undersigned is true and
correct.

      (u) understands that the Partnership will not register as an investment
company under the Investment Company Act by virtue of an exemption pursuant to
Sections 3(b)(1), 3(c)(1) or 3(c)(7). Accordingly, the protections afforded by
the Investment Company Act will not be available to the undersigned in
connection with an investment in the Partnership. Further, in this regard, if
the undersigned is a corporation, trust, partnership or other organization, the
undersigned represents that it is not being organized for the sole purpose of
investing in the Partnership.

      (v) covenants that, for so long as the undersigned is a Limited Partner of
the Partnership, the undersigned will not take any action or fail to take any
action that would cause any of the representations or warranties contained in
this Section 3 to be untrue.

4. Indemnification. The undersigned understands the meaning of the
representations made by the undersigned in this Subscription Agreement and
hereby agrees to indemnify and hold harmless the Partnership, the General
Partner, other Partners of the Partnership, and all persons deemed to be in
control of any of the foregoing, and to hold such persons and firms harmless
from and against, any and all loss, damage, liability or expense, including
costs and reasonable attorneys' fees, to which they may be put or which they may
incur by reason of, or in connection with (i) any misstatement,
misrepresentation or omission made by or on behalf of the undersigned with
respect to the matters about which representations and warranties are required
by the terms of this Subscription Agreement; or (ii) any breach of any such
warranties or any failure to fulfill any covenants or agreements set forth
herein or in the Partnership Agreement, including, but not limited to, any sale,
transfer or other disposition of all or any part of the Interests to or by the
undersigned in violation of the Securities Act or other applicable law. This
Subscription Agreement and the representations and warranties contained herein
and repeated in the Partnership Agreement shall be binding upon the heirs,
personal representatives, successors and assigns of the undersigned. All such
representations shall survive the delivery of this Subscription Agreement and
the purchase by the undersigned of any Interests.

5. Binding Nature. Upon acceptance by the General Partner of the subscription of
the undersigned, the undersigned agrees to become a Limited Partner of the
Partnership and to be bound by the terms of the Partnership Agreement. The
undersigned acknowledges and agrees that this subscription shall survive: (i)
changes in the transactions, documents and instruments described in the Offering
Materials which, in the aggregate, are not material or which are contemplated by
the Offering Materials, and (ii) the death, disability or incapacity of the
undersigned, and may not be canceled, terminated, modified or revoked by the
undersigned unless not accepted by the General Partner.


                                       4
<PAGE>

6. Miscellaneous. All pronouns contained herein and any variations thereof shall
be deemed to refer to the masculine, feminine or neuter, singular or plural, as
the case may be and as the context may require. This Subscription Agreement
constitutes the entire understanding of the parties with respect to the subject
matter hereof and supersedes all prior or contemporaneous agreements or
understandings of the parties related hereto. This Subscription Agreement may
only be modified or amended by an instrument in writing signed by all parties
hereto. All capitalized terms used but not defined in this Subscription
Agreement shall have the meanings set forth in the Offering Materials.



                                       5
<PAGE>

                            PHT STENT PARTNERS, L.P.
                      SIGNATURE PAGE AND POWER OF ATTORNEY

      The undersigned, desiring to become a Class A Limited Partner of PHT Stent
Partners, L.P. ("the Partnership"), by executing this Signature Page and Power
of Attorney, hereby executes, adopts and agrees to all terms, conditions and
representations of the Subscription Agreement and the Limited Partnership
Agreement of the Partnership (the "Partnership Agreement"). The undersigned
further constitutes and appoints the General Partner (and any additional or
substitute general partner), the Partners of the General Partner, and any
partner, member, officer or director thereof, the true and lawful
attorney-in-fact of the undersigned with full power of substitution, with such
attorney having full power and authority to act for the undersigned and, in the
undersigned's name, place and stead, (i) to execute, acknowledge, deliver, swear
to, certify, verify, publish, file and record any amendment or amendments to the
Partnership's Certificate of Limited Partnership for the purpose of adding the
undersigned and others as Limited Partners of the Partnership, as contemplated
by the Partnership Agreement (which amendments the undersigned hereby joins in
and executes), and of otherwise amending said Certificate and Partnership
Agreement, provided such actions are authorized in accordance with the
provisions of the Partnership Agreement; and (ii) to take any and all other
action on the undersigned's behalf as is authorized in said Partnership
Agreement. The power of attorney hereby granted shall be deemed to be coupled
with an interest, shall be irrevocable and shall survive the death or
incompetency of the undersigned.

Amount being funded as payment of initial Capital Contribution for Limited
Partnership Interests Purchased: $475,000
                                 --------

                                       6
<PAGE>

SUBSCRIBER(S):

Individuals sign below:

_________________________________                         ______________________
Signature                                                 Social Security Number


_________________________________                         Date: __________, 2004
Print Name


Partnerships, Corporations, Trusts and other entities sign below:

Name of Entity: TOUCHSTONE RESOURCES USA, INC.


33-0967974
-----------------------------
Taxpayer Identification Number


By:   /s/ Stephen P. Harrington                         Date: March 24, 2004
      --------------------------------                  ------------------------
Name: Stephen P. Harrington
Title: CEO

All Subscribers, please complete the following:

Residence Address (principal Place of Business)

_______________________________________________


                                             Mailing Address, if different from
                                             Residence Address:

                                             111 Presidential Boulevard 165
                                             Bala Cynwyd, PA 19004
                                             -----------------------------------
                                       7

<PAGE>

The foregoing subscription for PHT Stent Partners, LP. is hereby accepted this
______ day of _______ , 2004.


                                            BY: PHT Gas, LLC, General Partner



                                            By: /s/ Mark A. Bush
                                                ------------------------------
                                                 Mark A. Bush, Managing Member



                                       8