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     discharged prior to or at the Closing (all of which shall be included in
     the calculation of net asset value pursuant to Section 4.5);

          (ii) all of Seller's liabilities and obligations of the Business that
     have arisen in the ordinary course of the Business, consistent with past
     practice, between the Balance Sheet Date and the Closing Date that would be
     disclosed on a balance sheet prepared in accordance with GAAP and which are
     also liabilities and obligations of the type described in the example
     attached as Exhibit 2, but only if and to the extent that the same have not
     been paid or discharged prior to or at the Closing (all of which shall be
     included in the calculation of net asset value pursuant to Section 4.5);

          (iii)  all liabilities and obligations of the Seller in respect of the
     Contracts, commitments and arrangements, which Contracts, commitments and
     arrangements are specifically identified in any list called for by
     paragraphs (b) through (g) of Section 2.11 as it may be supplemented or
     updated by Seller with Contracts, commitments and arrangements entered into
     in the ordinary course of business prior to the Closing Date consistent
     with Sections 5.1 or 5.2, or are not required to be identified on any such
     list because of the term or amount involved or the descriptive limitations
     set forth in Section 2.11, except that the Purchasers shall not assume any:

               (A) liabilities or obligations of the aforesaid character
          existing as of the Balance Sheet Date and which under GAAP are or
          should be accrued or reserved for on a balance sheet or the notes
          thereto as a liability or obligation, if and to the extent that the
          same were not accrued or reserved for on the May Balance Sheet; or

               (B) liabilities or obligations of the character described in
          paragraphs (b) through (g) of Section 2.11 existing at the date of
          this Agreement, except for those items which are specifically
          identified on Schedule 2.11(b) through Schedule 2.11(g) as they may be
          supplemented or updated by Seller with Contracts, commitments or
          arrangements entered into in the ordinary course of business prior to
          the Closing Date, consistent with Sections 5.1 and 5.2; or

               (C) liabilities or obligations arising out of any breach by any
          Seller of any item of the character referred to in this Section
          4.2(b)(iii), including, without limitation, liabilities or obligations
          arising out of any Seller's failure to perform any Contract,
          commitment or arrangement in accordance with its terms prior to the
          Closing; or

               (D) any liabilities or obligations arising out of Seller's credit
          facility with Texas Commerce Bank; and

          (iv) liabilities and obligations of the Seller in respect of warranty
     claims by customers relating to the Business;

     In determining the liabilities and obligations of the Business to be
assumed by Enterra Sub pursuant to Section 4.2(b)(i) and (ii) hereof, to the
extent that there is a conflict between the methodology set forth in the example
attached as Exhibit 2 and GAAP, then the methodology set forth in the example
attached as Exhibit 2 shall control.

     (c) Other than the Assumed Liabilities, the Purchasers shall not assume or
be responsible for any liability of any Seller (collectively, the "Excluded
Liabilities").  (The parties acknowledge that it is possible that the Purchasers
may, in the operation of the Business after the Closing Date, incur liability
which may result in a Loss, other than as a result of contractual assumption of
liability, and that such Loss, if any, shall be governed in accordance with the
terms and provisions of Article X).  The obligations of the Purchasers under
Section 4.2(b) are subject to whatever rights the Purchasers may have under this
Agreement for a breach by any Seller of any representation, warranty, covenant
or agreement contained in this Agreement.  In addition to the foregoing, in no

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