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                                                                   Exhibit 10.11


[LOGO]                                           [1ST BUSINESS BANK LETTERHEAD]



November 14, 1996


Paul Chopra
Chief Executive Officer
COHR, Inc.
21540 Plummer Street
Chatsworth, CA 91311

Dear Paul:

You have requested, and the Bank has agreed, to increase our Revolving Line of
Credit to COHR, Inc. from the existing $2,000,000 to $5,000,000.  This letter
will serve to amend that certain Revolving Credit Agreement dated July 11, 1996
by and between COHR, Inc. ("Borrower") and 1st Business Bank ("Bank"), as
follows:

Section 1.1     Revolving Line of Credit. is deleted in its entirety and
replaced with the following:

"1.1  REVOLVING LINE OF CREDIT.  From the date the Borrower has satisfied all
conditions precedent as set forth in Section 2 hereof, to and until June 30,
1997, Bank agrees to make advances to Borrower from time to time up to a
maximum amount of FIVE MILLION DOLLARS ($5,000,000).  Borrower may borrow and
repay and reborrow all or part of the Line of Credit for its short term working
capital requirements of Borrower's business.  The indebtedness of Borrower to
Bank pursuant to the Line of Credit shall be evidenced by the Revolving Note on
the form used by Bank for such purposes.  Bank shall enter each amount borrowed
and repaid on the back of the Revolving Note, and such entries shall be PRIMA
FACIE evidence of the amount of the Line of Credit outstanding, but the failure
of the Bank to make any such notations shall not release Borrower from the
obligation to repay amount borrowed hereunder."

All other terms and conditions of the Revolving Credit Agreement shall remain
unchanged and in full force and effect.  Please sign below indicating your
agreement and acceptance of this amendment, and return an original signed copy
to my attention at your earliest convenience.  Thank you.

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Very truly yours,


1ST BUSINESS BANK


/s/  JOHN C. BLACK                              /s/  R.W. KUMMER, JR.
----------------------------                    ----------------------------
John C. Black                                   Robert W. Kummer, Jr.
Vice President                                  Chairman & C.E.O.


Agreed to and Accepted this 25th day of November, 1996
by COHR, INC.


/s/  PAUL CHOPRA                                /s/  UMESH MALHOTRA
----------------------------                    ----------------------------
Paul Chopra                                     Umesh Malhotra
Chief Executive Officer                         Chief Financial Officer




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[LOGO]

                                PROMISSORY NOTE
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BORROWER:       COHR, INC.              LENDER: 1st Business Bank
                21540 PLUMMER STREET            Headquarters
                CHATSWORTH, CA 91311            601 West Fifth St.
                                                Los Angeles, CA 90071
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<TABLE>
<CAPTION>
<S>                                     <C>                     <C>
PRINCIPAL AMOUNT:  $5,000,000.00        INITIAL RATE: 8.250%    DATE OF NOTE: NOVEMBER 20, 1996
</TABLE>

PROMISE TO PAY. COHR, INC. ("BORROWER") PROMISES TO PAY TO 1st BUSINESS BANK
("LENDER"), ON ORDER, IN LAWFUL MONEY OF THE UNITED STATES OF AMERICA, THE
PRINCIPAL AMOUNT OF FIVE MILLION & 00/100 DOLLARS ($5,000,000.00) OR SO MUCH AS
MAY BE OUTSTANDING, FROM TIME TO TIME WITH INTEREST THEREON FROM THE DATE OF
THE ADVANCE UNTIL PAID IN FULL.

PAYMENT.  BORROWER WILL PAY ALL OUTSTANDING PRINCIPAL PLUS ALL ACCRUED UNPAID
INTEREST ON OR BEFORE JUNE 30, 1997.  IN ADDITION, BORROWER WILL PAY, MONTHLY,
INTEREST, BEGINNING DECEMBER 31, 1996,AND ON THE LAST DAY OF EACH MONTH AFTER
THAT.  Interest on this Note is computed on a 365/360 simple interest basis;
that is, by applying the ratio or the annual interest rate over a year of 360
days, multiplied by the outstanding principal balance, multiplied by the actual
number of days the principal balance is outstanding.  Borrower will pay
Lender Principal and Interest at Lender's address shown above or at such other
place as Lender may designate in writing.  Unless otherwise agreed or required
by applicable law, payments will be applied first to any unpaid collection
costs and any late charges, then to any unpaid interest, and any remaining
amount to principal.

VARIABLE INTEREST RATE.  The interest rate on this Note is subject to change
from time to time based on changes in an index which is the 1st Business Bank
Reference Rate (the "Reference Rate"). Any change in the interest rate
resulting from a change in the Reference Rate shall be effective on and as of
the date of such change.  Lender will tell Borrower the current Reference Rate
upon Borrower's request.  Borrower understands that Lender may make loans based
on other rates as well.  THE REFERENCE RATE CURRENTLY IS 8.250% PER ANNUM.  THE
INTEREST RATE TO BE APPLIED TO THE UNPAID PRINCIPAL BALANCE OF THIS NOTE
WILL BE AT A RATE EQUAL TO THE REFERENCE RATE, RESULTING IN AN INITIAL RATE OF
8.250% PER ANNUM.  NOTICE: Under no circumstances will the interest rate on
this Note be more than the maximum rate allowed by applicable law.

PREPAYMENT.  Borrower may pay without penalty all or a portion of the amount
owed earlier than it is due.  Amounts repaid may be reborrowed in accordance
with the terms of this Note.

DEFAULT.  Borrower will be in default if any of the following happens: (a)
Borrower fails to make any payment when due.  (b) Borrower breaks any promise
Borrower has made to Lender, or Borrower fails to comply with or to perform
when due any other term, obligation, covenant, or condition contained in this
Note or any agreement related to this Note, or in any other agreement or loan
Borrower has with Lender.  (c) Any representation or statement made or
furnished to Lender by Borrower or on Borrower's behalf is false or misleading
in any material respect either now or at the time made or furnished.  (d)
Borrower becomes insolvent, a receiver is appointed for any part of Borrower's
property, Borrower makes an assignment for the benefit of creditors, or any
proceeding is commenced either by Borrower or against Borrower under any
bankruptcy or insolvency laws.  (e) Any creditor tries to take any of
Borrower's property on or in which Lender has a lien or security interest.
This includes a garnishment of any of Borrower's accounts with Lender.  (f) Any
guarantor dies or any of the other events described in this default section
occurs with respect to any guarantor of this Note.  (g) A material adverse
change occurs in Borrower's financial condition, or Lender believes the
prospect of payment or performance of the indebtedness is impaired.  (h) Lender
in good faith deems itself insecure.

ADDITIONAL DEFAULT PROVISION.  BORROWER WILL ALSO BE IN DEFAULT IF ANY OF THE
FOLLOWING HAPPENS: BORROWER'S FAILURE TO SUBMIT FINANCIAL STATEMENTS, TAX
RETURNS AND SUCH OTHER FINANCIAL INFORMATION TO THE HOLDER HEREOF WHEN
REQUESTED; THE OCCURRENCE OF AN EVENT WHICH CAUSES A MATERIAL ADVERSE CHANGE IN
BORROWER'S FINANCIAL CONDITION; THE GOOD FAITH BELIEF BY LENDER THAT THERE
EXISTS, OR THE ACTUAL EXISTENCE OF, ANY DETERIORATION OF BORROWER'S ABILITY TO
MEET BORROWER'S OBLIGATIONS TO LENDER OR TO BORROWER'S OTHER CREDITORS OR IN
THE VALUE OF ANY COLLATERAL SECURING THE OBLIGATIONS OF THE UNDERSIGNED
HEREUNDER; BORROWER CEASES TO EXIST OR ANY GENERAL PARTNER IN BORROWER CEASES
TO EXIST OR IS NO LONGER A GENERAL PARTNER IN BORROWER.

LENDER'S RIGHTS.  Upon default, Lender may declare the entire unpaid principal
balance on this Note and all accrued unpaid interest immediately due, without
notice, and then Borrower will pay that amount.  Upon Borrower's failure to pay
all amounts declared due pursuant to this section, including failure to pay
upon final maturity, Lender, at its option, may also, if permitted under
applicable law, increase the variable interest rate on this Note to 5.000
percentage points over the Reference Rate.  Lender may hire or pay someone else
to help collect this Note if Borrower does not pay.  Borrower also will pay
Lender all costs and expenses of collection.  This includes, subject to any
limits under applicable law, Lender's attorneys' fees and Lender's legal
expenses whether or not there is a lawsuit, including attorneys' fees and legal
expenses for bankruptcy proceedings (including efforts to modify or vacate any
automatic stay or injunction), appeals, and any anticipated post-judgment
collection services.  Borrower also will pay any court costs, in addition to
all other sums provided by law.  THIS NOTE HAS BEEN DELIVERED TO LENDER AND
ACCEPTED BY LENDER IN THE STATE OF CALIFORNIA.  IF THERE IS A LAWSUIT, BORROWER
AGREES UPON LENDER'S REQUEST TO SUBMIT TO THE JURISDICTION OF THE COURTS OF LOS
ANGELES COUNTY, THE STATE OF CALIFORNIA.  LENDER AND BORROWER HEREBY WAIVE THE
RIGHT TO ANY JURY TRIAL IN ANY ACTION, PROCEEDING, OR COUNTERCLAIM BROUGHT BY
EITHER LENDER OR BORROWER AGAINST THE OTHER.  THIS NOTE SHALL BE GOVERNED BY
AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF CALIFORNIA.

COLLATERAL.  This Note is secured by personal property collateral referred to
in a security/pledge agreement dated November 3, 1995.  Reference should be
made to such document for events of default which may accelerate payments of
this note.

ADVANCES.  Advances under this Note may be requested either orally or in writing
by borrower or by an authorized person.  Lender may, but need not; require that
all requests be confirmed in writing.  All communications, instructions, or
directions by telephone or otherwise to Lender are to be directed to Lender's
office shown above.  Borrower agrees to be liable for all sums either: (a)
advanced in accordance with the instructions of an authorized person or (b)
credited to any of Borrower's accounts with Lender.  The unpaid principal
balance owing on this Note at any time may be evidenced by endorsements on
this Note or by Lender's internal records, including daily computer print-outs.

PRIOR NOTE.  THIS IS AN INCREASED RENEWAL OF THAT CERTAIN PROMISSORY NOTE NO.
11455 DATED JULY 11, 1996.

GENERAL PROVISIONS.  Lender may delay or forgo enforcing any of its rights or
remedies under this Note without losing them.  Borrower and any other person
who signs, guarantees or endorses this Note, to the extent allowed by law,
waive any applicable statute of limitations, presentment, demand for payment,
protest and notice of dishonor.  Upon any change in the terms of this Note, and
unless otherwise expressly stated in writing, no party who signs this Note,
whether as maker, guarantor, accommodation maker or endorser, shall be released
from liability.  All such parties agree that Lender may renew or extend
(repeatedly and for any length of time) this loan, or release any party or
guarantor or collateral; or impair, fail to realize upon or perfect Lender's
security interest in the collateral; and take any other action deemed necessary
by Lender without the consent of or notice to anyone.  All such parties also
agree that Lender may modify this loan without the consent of or notice to
anyone other the party with whom the modification is made.

PRIOR TO SIGNING THIS NOTE, BORROWER READ AND UNDERSTOOD ALL THE PROVISIONS OF
THIS NOTE, INCLUDING THE VARIABLE INTEREST RAGE PROVISIONS.  BORROWER AGREES TO
THE TERMS OF THE NOTE AND ACKNOWLEDGES RECEIPT OF A COMPLETED COPY OF THE NOTE.

BORROWER:

COHR, INC.

By:
   -------------------------------------------
    AUTHORIZED OFFICER, TITLE

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