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cash in lieu of fractional shares of Parent Common Stock will be treated as 
outstanding EI stock on the date of the Merger. Moreover, shares of EI stock and
shares of Parent Common Stock held by EI shareholders and otherwise sold, 
redeemed, or disposed of prior or subsequent to the Effective Time of the Merger
will be so considered for purposes of this Agreement.

      2. The Controlling Shareholders represent that as of the date hereof each
owns shares of EI Common Stock in the amounts set forth on Exhibit "A" hereto.

      3. Each of the Controlling Shareholders agree that prior to the Effective
Time of the Merger, he will not sell, transfer or otherwise dispose of any EI
Common Stock.

      4. Subject to the terms of the Escrow Agreement, dated November 9, 1993,
between Parent, the Controlling Shareholders and Texas Commerce Bank--Houston,
each of the Controlling Shareholders agree that, for a period of one year after
the Effective Time of the Merger (the "Post-Merger Continuity Period") and
except for such a transaction by and among the Controlling Shareholders only, he
will not sell, transfer or otherwise dispose of an aggregate number of shares of
Parent Common Stock having a value, as of the date of the Merger, of more than
50 percent of the value of all of the issued and outstanding capital stock of EI
immediately prior to the Effective Time. For purposes of this Agreement, shares
of EI stock exchanged for cash or other property, surrendered by dissenters, or
exchanged for cash in lieu of fractional shares of Parent Common Stock will be
treated as outstanding EI stock on the date of the transaction. Moreover, shares
of EI stock and shares of Parent Common Stock held by EI shareholders and
otherwise sold, redeemed, or disposed of prior or subsequent to the Effective
Time of the Merger will be considered for purposes of this Agreement. Nothing in
this Agreement shall prohibit either of the Controlling Shareholders from
pledging any or all of the Parent Common Stock received by him pursuant to the
Merger, Purchase and Sale Agreement as collateral to secure bona fide
indebtedness of such Controlling Shareholder to a financial institution,
provided that such institution agrees to be subject to restrictions on the sale,
transfer or disposal of any such stock which are similar to those set forth
herein, provided, however, that no such restrictions shall apply to the
institution's ability to seize and dispose of the collateral in the event of
default.

      5. This Agreement shall be binding upon and shall be enforceable against
the successors of the Controlling Shareholders.

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