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TERMS OF THE ENERGY INDUSTRIES SALE

  General.  The material terms and provisions of the Purchase Agreement are
summarized below.  However, such description does not purport to be complete and
is qualified in its entirety by reference to the Purchase Agreement, a copy of
which is attached hereto as Appendix A.  Reference is made to the Purchase
Agreement for the complete terms and provisions thereof as well as for other
provisions that are not summarized below.

  Purchase Agreement.  The Purchase Agreement provides for the sale of
substantially all of the assets of Energy Industries.  Under the Purchase
Agreement, Enterra will also assume the following liabilities of Energy
Industries (the "Assumed Liabilities"): (i) certain current liabilities of
Energy Industries set forth on its May 31, 1995 balance sheet which have not
been discharged prior to the closing date, (ii) certain current liabilities of
Energy Industries that have arisen in the ordinary course of Energy Industries'
Business, consistent with past practice, since May 31, 1995 which would be
described on a balance sheet prepared in accordance with generally accepted
accounting principles which have not been discharged prior to the closing date,
(iii) certain contracts, commitments and arrangements of Energy Industries, and
(iv) liabilities of Energy Industries with respect to warranty claims by
customers.

  Purchase Price.  At the Closing, Enterra will, subject to the terms and
conditions of the Purchase Agreement, purchase from the Company all of the
Assets and assume the Assumed Liabilities. The Purchase Price of $130 million is
payable to the Company in immediately available funds on the Closing Date,
increased or decreased, as the case may be, by the amount that the net asset
value of Energy Industries on the Closing Date is greater than, or less than, as
the case may be, $106,623,968, the amount of Energy Industries' net asset value,
as agreed to by the parties, on May 31, 1995.  Under the terms of the Purchase
Agreement, within 30 days after the Closing Date, Enterra will deliver to the
Company its own calculation of the net asset value of Energy Industries on the
Closing Date and the Company must notify Enterra of its agreement or
disagreement with such calculation.  If the parties cannot resolve any
disagreement on the net asset value calculation, then such calculation will be
finally determined by two independent public accounting firms chosen by the
Company and Enterra.  Once the post-closing reconciliation of the net asset
value is determined, Enterra or the Company, as the case may be, must pay to the
other within three days such reconciliation amount.

  Representations and Warranties.  In the Purchase Agreement, the Company makes
representation and warranties regarding Energy Industries, including, without
limitation, representations and warranties regarding Energy Industries'
financial condition, liabilities, agreements, title to assets, litigation,
environmental matters and compliance with laws and regulations.  The Company
considers such representations to be normal and customary in a transaction of
this type.  Enterra has also made certain normal and customary representations
and warranties to the Company in the Purchase Agreement.

  The representations and warranties set forth in the Purchase Agreement will,
subject to certain exceptions, terminate one year after the Closing Date.

  Conditions to Closing.  The obligations of Enterra to consummate the Energy
Industries Sale are conditioned upon the: (a) truth and correctness in all
material respects of all representations and warranties of the Company made in
the Purchase Agreement on the date of the Purchase Agreement and on the closing
date, (b) performance in all material respects by the Company of all obligations
and compliance with all covenants and conditions in the Purchase Agreement, (c)
delivery of proper instruments for the transfer of the Assets, (d) receipt by
Enterra of evidence of required third party consents and governmental
authorizations, and (e) receipt of customary closing certificates and legal
opinions.

  The obligations of the Company to consummate the Energy Industries Sale are
conditioned upon the: (a) truth and correctness in all material respects of all
representations and warranties of Enterra in the Purchase Agreement on the date
of the Purchase Agreement and on the closing date, (b) performance in all
material respects by Enterra of all obligations and compliance with all
covenants and conditions in the Purchase Agreement, (c) receipt of the Purchase
Price, (d) execution and delivery of instruments for the assumption of the
Assumed Liabilities, and (e) receipt of customary closing certificates and legal
opinions.

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