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                                                                   EXHIBIT 10.2a


                              STANDSTILL AGREEMENT

         This Standstill Agreement (the "Agreement") is entered into by and
between Paul Chopra, an individual ("Chopra"), on the one hand, and COHR Inc., a
Delaware corporation ("COHR"), on the other hand. (Chopra and COHR are
collectively referred to as "the Parties".) The Effective Date of this Agreement
is April 3, 1998.

                                    Recitals

         A. Chopra has been at various times a director, officer and employee of
COHR.

         B. The Parties entered into an Employment Agreement dated January 1,
1996 (the "Employment Agreement").

         C. Potential disputes have arisen between the Parties as to their
rights and obligations under the Employment Agreement. The Parties now desire to
postpone any potential dispute arising out of or relating to any termination of
Chopra under the Employment Agreement to permit further discussions among the
Parties.

                                    Agreement

          1.       Ending Date

         The "Ending Date" of this Agreement shall be the earliest of the
following:

         (a) Fourteen (14) days following the date on which either party gives
written notice to the other party that it is terminating this Agreement;

         (b) November 10, 1998.

All rights and obligations existing prior to this Agreement or arising under
this Agreement shall survive the termination of this Agreement.

          2.       Effective Period

         The period of time from the Effective Date to the Ending Date shall be
the "Effective Period" of this Agreement.

          3.       Standstill Provision

         Any passage of time during the Effective Period will not waive or
prejudice the rights of either of the Parties with respect to any termination of
Chopra's employment or the consequences thereof. As of the Ending Date, COHR
shall have all rights and obligations that it had as of the Effective Date,
including but not limited to all rights that COHR has or may have with respect
to its ability to terminate Chopra for cause. As of the Ending Date, Chopra
shall have all rights and obligations that he had as of the Effective Date,
including but not limited to all objections that Chopra has or may have with
respect to any alleged ability of COHR to terminate Chopra for cause.



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          4.       Certain Continuing Benefits

                  (a) During the Effective Period, COHR will continue to pay the
premiums on all medical and dental insurance coverages for Chopra and his family
for which COHR is currently paying the premiums.

                  (b) During the Effective Period, COHR will pay Chopra salary
of $10,000 per month (in two equal installments, on the first and fifteenth of
each month, commencing April 15, 1998).

                  (c) During the Effective Period, Chopra may continue to have
use of the company car currently in his possession, and COHR will continue to
make the payments that it is currently making for the leasing of that car.

                  (d) Except as set forth in subparagraphs 4 (a), (b) and (c),
COHR shall not be obligated to pay Chopra any salary or employment benefits, nor
to make any lump-sum payment under the Employment Agreement, during or for the
Effective Period. Except as set forth in this Agreement, no obligations will be
deemed to arise or accrue during the Effective Period.

          5.       Notices

                  (a) Any notice to COHR required or permitted hereunder shall
be given in writing to the Secretary of the Company, either by personal service
or by registered mail, postage prepaid, addressed to the Company at its then
principal place of business, with copy to its attorney, John Spiegel, at Munger,
Tolles & Olson LLP, 355 South Grand Avenue, 35th Floor, Los Angeles, CA 90071.

                  (b) Any notice to Chopra required or permitted hereunder shall
be given in writing to Chopra, either by personal service or by registered mail,
postage prepaid, and if mailed shall be addressed to the Chopra at his home
address then shown in the files of the Company, with copy to his attorney,
Burton Ward, at Goldstein & Ward, Inc., 440 East La Habra Boulevard, La Habra,
CA 90631.

          6.       Arbitration and Attorney Fees

         Either party hereto shall have the right, in addition to all other
rights and remedies provided by law, to seek arbitration in Los Angeles County,
California, under the rules of the American Arbitration Association, in the
event of any dispute concerning this Agreement. If any remedy or relief is
sought by either party hereunder, the prevailing party shall, in addition to the
remedy or relief so obtained, be entitled to recover from the other party
attorneys fees and expenses incurred in that dispute.



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          7.       Integration

         This Agreement contains the entire agreement between the parties with
respect to the subject matter hereof and supersedes all prior agreements,
understandings, commitments and practices, whether written or oral, except that
this Agreement is an amendment of that certain Employment Agreement dated
January 1, 1996. No amendments to this Agreement may be made except by a writing
signed by both parties.

         This Agreement may be executed in counterparts, each of which will be
an original agreement. The undersigned have executed this Agreement as of the
date first above written.


Chopra                                       COHR Inc.


/s/ Paul Chopra                              By  /s/ Lynn P. Reitnouer
-----------------------------                   -------------------------------
Paul Chopra                                     Lynn P. Reitnouer
                                                Chairman of the Board



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