Exhibit 99.1
Contact:       Gary N. Patten
               Chief Financial Officer
               714/921-2640

               Roger S. Pondel
               Pondel Parsons & Wilkinson
               310/207-9300



                Unit Instruments Announces Revised Merger Terms

YORBA LINDA, CA - November 10, 1998 - Unit Instruments, Inc. (Nasdaq: UNII)
announced today that it has agreed to revised merger consideration terms with
United States Filter Corporation (NYSE: USF).

          Under the revised terms, as specified in a Second Amendment to
Agreement and Plan of Merger dated as of November 10, 1998, the ratio at which
shares of Unit common stock will be exchanged into shares of U.S. Filter common
stock will be calculated by dividing the revised merger consideration by the
average price of U.S. Filter common stock over a 20 trading day period ending on
the fifth trading day preceding the closing.  The exchange ratio will be $10.00
divided by the average price of U.S. Filter common stock if the average U.S.
Filter share price is equal to or greater than $22.00.  If the average U.S.
Filter share price is equal to or less than $12.00, then the exchange ratio
shall be determined by dividing $8.00 by the average U.S. Filter share price.
If the average U.S. Filter share price is greater than $12.00 but less than
$22.00, then the exchange ratio will be determined by dividing an amount ranging
between $8.00 and $10.00 (such amount to be determined in accordance with a
formula set forth in the Second Amendment) by the average U.S. Filter share
price.  U.S. Filter has the right to terminate the Merger Agreement if the
average U.S. Filter share price is below $11.00.

          The full text of the Second Amendment has been filed today with the
Securities and Exchange Commission as an exhibit to a current report of Unit on
Form 8-K, and may be viewed on the SEC's web site at www.sec.gov.  A copy of the
Second Amendment may also be obtained by contacting Gary N. Patten, corporate
secretary of Unit Instruments at 714/921-2640.

          This news release contains forward-looking statements that involve
risks and uncertainties that could cause actual results to differ materially
from those projected.  Such risks and uncertainties include, but are not limited
to, the price of U.S. Filter stock during the twenty (20) day average pricing
period, the failure of one or more conditions to consummate the merger, business
activity levels in both the domestic and international semiconductor equipment
markets, the magnitude and duration of the current industry downturn, the
company's dependence on a few large customers, performance and industry
acceptance of the company's products, specifically MultiFlo(TM) and Safe
Delivery Source (SDS(TM)) MFCs, product pricing pressures, performance and
profitability under fixed price contracts, expenses for extended product
warranty, adequacy of cost reduction programs, the successful commercialization
of the Z-Bloc(TM) Modular Gas System, development of a viable industrial sales
base, failure to remediate Year 2000 issues, and other challenges from the
company's competition.  Certain of these and other risks are detailed from time
to time in Unit Instruments' filings with the Securities and Exchange

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Commission, including the Annual Report on Form 10-K for the fiscal year ended
May 31, 1998, Current Report on Form 8-K dated July 2, 1998 and Quarterly Report
on Form 10-Q dated August 29, 1998.  In light of the significant risks and
uncertainties inherent in the forward-looking information included herein, there
can be no assurance that the results contemplated by such statement will be
achieved.  The company assumes no obligation to update the information in this
release.

          Unit Instruments, Inc. is a leading manufacturer of mass flow
controllers and gas delivery systems for the semiconductor and industrial
markets.  The company maintains support and service centers throughout North
America, Europe and the Pacific Rim.  Unit Instruments is traded on the Nasdaq
National Market under the symbol UNII.  Unit's web site is located at
http://www.unit.com.

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