Document:

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                                                                   EXHIBIT 10.56

                                 AMENDMENT TO
                           INVESTOR RIGHTS AGREEMENT
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     THIS AMENDMENT TO INVESTOR RIGHTS AGREEMENT is entered into as of the 25th
day of August 2000 (this "Amendment"), by and among OVERHILL FARMS, INC., a
                          ---------
Nevada corporation (the "Company"), POLYPHASE CORPORATION, a Nevada corporation
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("Parent"), and LEVINE LEICHTMAN CAPITAL PARTNERS II, L.P., a California limited
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partnership ("LLCP").
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                            R  E  C  I  T  A  L  S
                            -  -- -  -  -  -  -  -

     A.  OVERHILL L.C. VENTURES, INC., a California corporation ("Overhill
                                                                  --------
Ventures"), and the parties hereto entered into a Securities Purchase Agreement
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dated as of November 24, 1999 (the "Securities Purchase Agreement"), pursuant to
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which, among other things, the Company issued to LLCP, and LLCP purchased from
the Company, the Securities, all on the terms and subject to the conditions set
forth therein.  Unless otherwise indicated, all capitalized terms used and not
otherwise defined herein have the meanings specified in the Securities Purchase
Agreement.

     B.  In connection with the closing of the transactions contemplated by the
Securities Purchase Agreement, the parties hereto entered into an Investor
Rights Agreement dated as of November 24, 1999 (the "Investor Rights
                                                     ---------------
Agreement"), pursuant to which, among other things, the Company and Parent
granted to the Purchaser certain investment monitoring, voting and other rights
as more fully set forth therein.

     C.  Overhill Ventures and the parties hereto are entering into a Consent
and First Amendment to Securities Purchase Agreement dated as of August 23, 2000
(the "Consent and Amendment"), pursuant to which, among other things, LLCP is
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consenting to the Transactions (as such term is defined in the Consent and
Amendment) and the parties thereto are amending certain provisions of the
Securities Purchase Agreement, all on the terms and subject to the conditions
set forth therein.

     D.  It is a condition to the effectiveness of LLCP's consent and the
amendments to the Securities Purchase Agreement under the Consent and Amendment
that the Company and Parent execute and deliver this Amendment.

                           A  G  R  E  E  M  E  N  T
                           -  -  -  -  -  -  -  -  -

     NOW, THEREFORE, in consideration of the foregoing and the mutual covenants,
conditions and provisions contained herein, and for other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto hereby agree as follows:
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     1.  Amendment of Section 1.5 (Consulting Fees).  Section 1.5 (Consulting
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Fees) of the Investor Rights Agreement is hereby amended by adding the following
new clause (d) at the end of such Section:

              "(d)  In addition, the Company agrees to pay to LLCP Inc. a non-
         refundable monthly consulting fee in the amount of $6,000 for each
         calendar month (or portion thereof) during the period commencing on
         August 1, 2000, and ending on the date upon which all Obligations under
         the Note have been paid in cash in full. Each monthly consulting fee
         shall be due and payable in advance on the first Business Day of each
         such calendar month; provided, however, that the monthly consulting fee
                              --------  -------
         due hereunder for the month of August 2000 shall be equal to $1,355
         (which represents a pro rated monthly consulting fee based upon the
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         number of days remaining in such month from and including August 25,
         2000) and shall be due and payable on the first Business Day of the
         month of September 2000."

     2.  Full Force and Effect.  This Amendment amends the Investor Rights
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Agreement on and as of the date hereof, and the Investor Rights Agreement shall
remain in full force and effect as amended hereby.  The Investor Rights
Agreement, as amended by this Amendment, and all other Investment Documents are
hereby ratified and affirmed by the parties hereto in all respects.

     3.  Governing Law.  In all respects, including all matters of construction,
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validity and performance, this Amendment shall be governed by, and construed and
enforced in accordance with, the laws of the State of California applicable to
contracts made and performed in such state, without regard to principles
regarding choice of law or conflicts of laws.

     4.  Counterparts.  This Amendment may be executed in any number of
         ------------
counterparts and by facsimile, each of which shall be deemed an original, but
all of which taken together shall constitute one and the same instrument.

                  [REST OF THE PAGE INTENTIONALLY LEFT BLANK]
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     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to
Investor Rights Agreement to be executed and delivered by their duly authorized
representatives as of the date first written above.

                        COMPANY
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                        OVERHILL FARMS, INC., a Nevada corporation

                        By:
                           ---------------------------------------------
                                James Rudis
                                President and Chief Executive Officer

                        PARENT
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                        POLYPHASE CORPORATION, a Nevada corporation

                        By:
                           ---------------------------------------------
                                James Rudis
                                President and Chief Executive Officer

                        LLCP
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                        LEVINE LEICHTMAN CAPITAL PARTNERS II, L.P.,
                        a California limited partnership

                        By:  LLCP California Equity Partners II, L.P., a
                             California limited partnership, its General Partner

                             By:  Levine Leichtman Capital Partners, Inc., a
                                  California corporation, its General Partner

                                  By:
                                     -------------------------------------
                                          Arthur E. Levine
                                          President<PAGE>

                                                                   EXHIBIT 10.11

                             Employment Agreement
                             --------------------

     This Employment Agreement (the "Agreement") is entered into by and between
RETRACTABLE TECHNOLOGIES, INC., a Texas corporation with its principal offices
at 511 Lobo Lane, Little Elm, Texas 75068 (the "Company") and PHILLIP L. ZWEIG
(the "Employee") in consideration of the following mutual covenants and
conditions contained in this Agreement:

     1.  Duties. The Company and Employee agree that, during the Term of this
         ------
Agreement, Employee shall be employed by the Company to obtain and author
favorable coverage of the Company and issues important to the Company in local
and national media outlets throughout the United States. Employee shall provide
these services in Texas, New York, and such other locations as the Company and
Employee consider desirable. The Company shall pay for Employee's reasonable
travel, entertainment and related expenses in connection with the performance of
his duties for the Company, and shall provide Employee with company credit and
phone charge cards for these expenses. Employee shall provide an expense report
for all business expenses, whether paid for by the Employee or by Company credit
card. This Agreement is a contract for the performance of personal services, and
no right or obligation of Employee under this Agreement may be transferred by
Employee without the written agreement of the Company.

         It is understood that Employee may from time to time engage in writing
for publication, including books, film scripts, and articles unrelated to the
business of the Company, and that Employee will be permitted to continue to
engage in these activities on his own time. Employee agrees that should Employee
choose to work on any book or script about the Company, Employee will not
proceed with any efforts related to such book or script without first obtaining
written permission from the Company. Further Employee agrees that Employee will
not cause such book to be published prior to final resolution of the Company's
antitrust litigation.

     2.  Compensation. The Company shall pay Employee a biweekly salary of
         ------------
$4,615.38 during the term of this Agreement. In addition, the Company shall,
subject to approval by the Company's Compensation and Benefits Committee, grant
Employee non-qualified options to purchase 10,000 shares of stock in the Company
under the 1999 Stock Option Plan incorporated herein as Attachment "C". Other
fringe benefits which are afforded to most other full time employees (including
but not limited to medical insurance and paid vacation and sick leave) shall be
provided by the Company to Employee on the same terms that those benefits are
made available to most other employees. Employee shall be considered for bonuses
at the same time and on the same terms as other management employees.

Employment Agreement - Page 1 of 4
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     3.  Term and Termination of Agreement. This agreement is made for a period
         ---------------------------------
of six (6 months) commencing on December 13, 2000 and ending on June 12, 2001
(the "Term" of this Agreement). Either party may, at their option, terminate
this Agreement upon not less than 30 days' written notice. Employee's right to
further employment by the Company shall automatically cease at the end of the
Term of this Agreement. The Company and Employee may agree to renew or extend
Employee's contractual right to continued employment beyond the expiration of
the Term of this Agreement, but may only do so in a writing which is separate
from this document and includes at least the following: i) a clear statement of
the new date on which Employee's right to further employment shall automatically
cease; ii) a clear statement of the number of additional shares, if any, for
which the Company shall grant Employee options and the date on which such
options shall vest; and iii) the signatures of both the Company's president and
the Employee. Should a court of competent jurisdiction nevertheless find a
renewal or extension of this Agreement or other obligation of continued
employment in the absence of such a writing, the period of such renewal,
extension or obligation (and of any renewals thereof) shall be limited in
duration to fourteen (14) days and no additional options shall be granted in
connection therewith.

     4.  Trade Secrets, Company Records, Non-Competition. A copy of an
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acknowledgment of receipt of the Company's Policy Manual and assignment of
intellectual property rights is incorporated herein as Attachment "A". A copy of
a Confidentiality Agreement signed by Employee is incorporated herein as
Attachment "B". All Company-related records and documents created or acquired by
Employee in the course of his employment by Company or under the possession or
control of Employee shall be considered to be the exclusive property of the
Company and shall, upon the conclusion of Employee's employment by the Company
for any reason, be promptly returned by Employee to Company.

         It is anticipated that Employee will, during his employment by the
Company, be privy to much confidential information at the highest level of the
Company about its marketing and healthcare policy strategies in a highly
competitive industry and the Company's understanding of the issues involved in
those strategies. During Employee's employment by the Company and for a period
of three (3) years thereafter, Employee shall not write articles about the
Company for independent publications and shall not provide any services relating
to marketing strategy, healthcare policy, publicity or media coverage, or any
other services in the United States to any manufacturer of needle products,
healthcare group purchasing organization, or other individual or business entity
that is in direct competition with the business of the Company. Should a court
of competent jurisdiction find any portion of this restriction to be
unenforceable, such portion shall be reformed to the smallest extent required to
cause the restriction to be enforceable.

Employment Agreement - Page 2 of 4
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         Employee hereby stipulates and acknowledges his understanding that
each paragraph in this section is an integral part of this Agreement and that
the Company's willingness to grant stock options to Employee depends upon
Employee's agreement to each paragraph in this section.

     5.  Indemnification for Libel and Defamation. The Company agrees to hold
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Employee harmless for any statements, whether actual or alleged, that Employee
makes to the press or in public concerning the Company's competitors, group
purchasing organizations, or other individuals or organizations related directly
or indirectly to the Company's business. The Company will assume the full cost
of any and all such legal actions, litigation or judgment involving Employee,
even if such legal actions, litigation, or judgments occur after Employee has
left the Company.

     7.  Waiver. No waiver of any term of this Agreement shall be valid unless
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executed in writing and signed by the party to be bound thereby, and then only
to the extent specified in such waiver. No waiver of any term of this Agreement
shall be construed as a waiver of any other term of this Agreement, and no
present waiver of any term of this Agreement shall be construed as a future
waiver of such term.

     8.  Governing Law. The rights of the parties shall be governed by, and this
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Agreement shall be interpreted in accordance with, the laws of the State of
Texas and the federal law applicable therein; provided, however, that the law of
Texas regarding choice of law shall be disregarded to the extent that it would
apply the law of a different jurisdiction. Any legal proceeding relating to this
Agreement shall be filed in a court of general jurisdiction in the State of
Texas and the parties hereby waive any other venue. No recovery in any legal
proceeding relating to this Agreement may be based in whole or in part upon
conduct which occurred more than one (1) year prior to the filing of such legal
proceeding, but shorter time may be specified by applicable law.

     9.  Sole Agreement. This Agreement and its Attachments "A-C" contain the
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entire agreement between the Company and Employee and supersede any and all
prior agreements, understandings and arrangements, whether oral or written,
between the Company and Employee. Employee represents and warrants to the
Company that Employee is not relying upon, and has not been induced to execute
or deliver this Agreement by, any statement, promise, agreement, understanding,
arrangement or inducement other than those which are specifically set forth in
the Agreement. No modification of this Agreement shall be effective unless made
in writing and signed by the party against whom enforcement of the modification
is sought. Employee understands that no employee or representative of the
Company is authorized to modify this Agreement orally or in any other manner
except in writing. This Agreement is executed in two (2) counterparts, each of
which shall be deemed an original for all purposes.

Employment Agreement - Page 3 of 4
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          IN WITNESS WHEREOF, the parties hereto have each executed this
Agreement on the date and at the location written below.

COMPANY                                 EMPLOYEE
Retractable Technologies, Inc.          Phillip L. Zweig

/s/ Thomas J. Shaw                      /s/ Phillip L. Zweig
------------------------------          ---------------------------------
by Thomas J. Shaw,
President and CEO

Date:     12/21/00                Date:    12/21/00
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Location:  Little Elm, TX          Location:  New York City, NY
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Employment Agreement - Page 4 of 4

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