Exhibit 4.13

Series F Debenture - 


NEITHER THIS 7% SERIES F ADDITIONAL PIK CONVERTIBLE DEBENTURE DUE MAY 31, 1999
(THE "DEBENTURE"), THE ADDITIONAL DEBENTURES ("ADDITIONAL DEBENTURES") NOR THE
SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF THIS DEBENTURE OR ANY
ADDITIONAL DEBENTURE HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE
"ACT"), AND NEITHER THIS DEBENTURE NOR ANY ADDITIONAL DEBENTURE NOR SUCH SHARES
MAY BE SOLD, ENCUMBERED OTHERWISE TRANSFERRED EXCEPT PURSUANT TO AN EFFECTIVE
REGISTRATION STATEMENT UNDER SUCH ACT OR AN EXEMPTION FROM SUCH REGISTRATION
REQUIREMENT, AND, IF AN EXEMPTION SHALL BE APPLICABLE, THE HOLDER SHALL HAVE
DELIVERED AN OPINION OF LEGAL COUNSEL ACCEPTABLE TO THE COMPANY THAT SUCH
REGISTRATION IS NOT REQUIRED.




                                UNSI Corporation

                Series F 7% Additional PIK Convertible Debenture
                                Due May 31, 1999

$__________                                                  New York, New York
                                                                   May 31, 1996



         UNSI Corporation, a corporation duly organized and existing under the
laws of the State of Delaware (herein called the "Company"), for value received,
hereby promises to pay to the order of ______________ or registered assigns (the
"Registered Holder"), the principal sum of ______________________ Dollars
($_________) on May 31, 1999 or such earlier date as may be applicable pursuant
to Article 2 of this Debenture (the "Maturity Date"). Simple interest shall
accrue on the unpaid principal amount of this Debenture from the date hereof
until Maturity (computed on the basis of a 365 day year, using the number of
days actually elapsed) at the rate of seven (7%) percent per annum, and shall be
payable in arrears on May 31 of each year, commencing May 31, 1997 and at
Maturity. Payments of principal and interest shall be made at the Payment
Address (as such term is defined herein) in lawful money (except as otherwise
provided herein) of the United States of America.

                  This Debenture is one of an authorized issue of the Company's
Series F 7% Additional PIK Convertible Debentures due May 31, 1999 (the
"Debentures"), issued pursuant to Article 1 of the Prior Debentures (as defined)
in satisfaction of the interest payment obligation that

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has accrued on the Prior Debentures from June 1, 1995 through May 31, 1996. The
term "Prior Debentures" refers to the 7% Pay-In-Kind Convertible Debentures due
May 31, 1999 issued as of June 1, 1994 pursuant to the Private Placement
Memorandum dated as of April 5, 1994, as amended (the "Memorandum"). Except as
specifically stated herein or as the context otherwise requires, the term
"Debentures" shall include the Debentures, the Prior Debentures, the Series E
Debentures dated May 31, 1995 and the Additional Debentures (as such term is
defined in the Prior Debentures).


                                   ARTICLE 1

              The Company's Right to Deliver Additional Debentures
                 in Lieu of Cash in Payment of Accrued Interest

(a) Delivery of Additional Debentures in Payment of Accrued Interest. At the
option of the Company, any interest accruing on the Debentures may be paid in
Additional Debentures in the manner set forth below; provided, however, that no
Additional Debenture may be issued in satisfaction of any interest payment made
less than one hundred eighty (180) days prior to May 31, 1999. The Additional
Debentures shall be in the same form as the Debentures provided, however, that
the Additional Debentures shall (i) bear interest at the greater of seven
percent (7%) per annum or the then applicable federal rate for debt instruments
(compounded annually) with the maturity of the applicable Additional Debenture;
(ii) bear interest from the issuance date of such Additional Debentures (i.e.,
the applicable interest payment date) and not from the date hereof; and (iii)
shall contain such other terms and conditions (or eliminate terms and conditions
contained herein) as the Company, in good faith, determines is appropriate.

(b) Election to Deliver Additional Debentures. The Company may exercise its
option to deliver Additional Debentures in payment of all or any part of such
accrued interest by notice to the Registered Holders of the Debentures on the
applicable interest payment date, which notice shall be dated not later than
applicable interest payment date, shall state that the Company has elected to
deliver Additional Debentures in lieu of cash payment of all or part of such
accrued interest and shall be accompanied by the Additional Debentures and a
check in payment of any part of the accrued interest being paid in cash.

(c) Amount of Additional Debentures Deliverable. The principal amount of
Additional Debentures deliverable pursuant to this Article 1 shall be equal to
the amount of interest payable on this Debenture on the applicable interest
payment date less the amount of interest paid in cash (if any) on this Debenture
on such interest payment date.

(d) Payment of Interest in Cash or Additional Debentures.  The Company may pay
all or any part of accrued interest on this Debenture by delivery of Additional
Debentures.  Any payment of interest made partly in cash and partly in
Additional Debenture shall be made pro rata to each Registered

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Holder of the Debentures on the applicable interest payment date; provided,
however, that if the Company has not satisfied any condition to the issuance of
Additional Debentures to any particular Registered Holder(s) as required under
paragraph (e) of this Debenture, then the Company shall pay interest wholly in
cash to such Registered Holder(s).

(e) Conditions to Delivering Additional Debentures. The right of the Company to
deliver Additional Debentures pursuant to this Article 1 with respect to any
payment of interest to any Registered Holder shall be subject to the conditions
that (i) the Additional Debentures shall have been registered or qualified or,
in the opinion of counsel to the Company, exempt from registration or
qualification under federal securities laws; and (ii) the Additional Debentures
and shares of Common Stock issuable upon conversion of such Additional
Debentures have been duly authorized and would, upon issuance, be validly
issued, fully paid and non-assessable.


                                   ARTICLE 2

                            Default and Acceleration

                  If the Company shall fail to pay the principal of, or interest
on, the Debentures as and when due and payable, then, the Registered Holders of
at least fifty (50%) percent of the then outstanding principal amount of
Debentures (inclusive of the principal amount outstanding on the Prior
Debentures, the Series E Debentures and the Additional Debentures) may, by
written notice to the Company, declare the principal amount of all of the
Debentures (including the Prior Debentures, the Series E Debentures and the
Additional Debentures), together with all interest thereon, to be forthwith due
and payable, whereupon, unless such default in payment is cured within 30 days
of the date such notice is given, the date of such notice shall become the new
Maturity Date and the principal amount of all of the Debentures (including the
Prior Debentures, the Series E Debentures and the Additional Debentures) and all
such interest shall become and be forthwith due and payable without presentment,
demand, protest, or further notice of any kind, all of which are hereby
expressly waived by the Company.


                                   ARTICLE 3

                           Conversion of Debentures.

(a) Optional Conversion of Debentures. Subject to and upon compliance with the
provisions of this Article 3, the Registered Holder of this Debenture shall have
the right, at such Holder's option, at any time prior to 5:00 P.M., New York
City time on May 31, 1999 to convert the unpaid principal amount of this
Debenture into fully paid and nonassessable shares of Common Stock of the
Company. Shares of Common Stock issuable upon conversion of this Debenture, the
Prior

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Debentures, the Series E Debentures and all Additional Debentures shall be
referred to herein as "Debenture Shares."

(b) Exercise of Conversion Privilege; Issuance of Common Stock on Conversion.

         (i) In order to exercise the optional conversion privilege, the holder
of this Debenture shall surrender the Debenture at the address of the Company
specified herein, and together with notice specifying the portion of the
principal amount of this Debenture which the Registered Holder elects to
convert. The number of shares of Common Stock issuable upon conversion shall be
determined by dividing the amount of principal being converted by the conversion
price in effect at such time. Such Registered Holder shall thereupon be deemed
the holder of the shares of Common Stock so issued, and the principal amount on
the Debenture, to the extent so converted, shall be deemed to have been paid in
full. If a Debenture shall have been converted in part, the Registered Holder
shall be entitled to a new Debenture representing the unpaid principal balance
of such Debenture remaining after deducting the principal amount of the
Debenture converted.

         (ii) As promptly as practicable after the surrender of such Debenture
and the receipt of such notice, the Company shall issue and shall deliver at
such office to such holder, or on his written order, a certificate or
certificates for the number of full shares issuable upon the conversion of such
Debenture or portion thereof in accordance with the provisions of this Article
3. The person in whose name any certificate or certificates for shares of Common
Stock shall be issuable upon conversion shall be deemed to have become on said
conversion date the holder of record of the shares represented thereby.

         (iii) Any accrued but unpaid interest with respect to a Debenture
converted pursuant to this Article 3 shall be paid upon such conversion, either
in cash or, in lieu of cash, in such number of shares of the Company's Common
Stock as equals the interest payment due at the date of conversion divided by
the conversion price in effect on such date.

(c) No Cash Payments in Lieu of Fractional Shares. No fractional shares of stock
or scrip representing fractional shares shall be issued upon conversion of
Debentures. In the event the conversion of any Debenture would result in the
issuance of a fractional share, the number of shares issuable upon such
conversion shall be rounded up to the nearest whole share. If more than one
Debenture shall be surrendered for conversion at one time by the same holder,
the number of full shares which shall be issuable upon conversion shall be
computed on the basis of the aggregate principal amount of the Debentures (or
specified portions thereof to the extent permitted hereby) so surrendered.

(d) Conversion Price.  The conversion price shall be $.4524 per share, subject
to adjustment as provided herein.


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(e) Adjustment of Conversion Price.  The conversion price shall be adjusted from
time to time as follows:

         (i) In case the Company shall on any one or more occasions after the
date of the Memorandum (1) pay a dividend or make a distribution in shares of
its capital stock (whether shares of Common Stock or of capital stock of any
other class) to all holders of its Common Stock, (2) subdivide its outstanding
Common Stock, or (3) combine its outstanding Common Stock into a smaller number
of shares, the conversion price in effect immediately prior thereto shall be
adjusted so that the holder of any Debenture thereafter surrendered for
conversion shall be entitled to receive the number of shares of capital stock of
the Company which he would have owned or have been entitled to receive after the
happening of any of the foregoing events had such Debenture been converted
immediately prior to the happening of such event. Any adjustment made pursuant
to this subparagraph (e)(i) of this Article 3 shall become effective immediately
after the record date in the case of a dividend or distribution or the effective
date in the case of a subdivision or combination. If, as a result of an
adjustment made pursuant to this subparagraph (e)(i) of this Article 3, the
holder of any Debenture thereafter surrendered for conversion shall become
entitled to receive shares of two (2) or more classes of capital stock of the
Company, the Board of Directors (whose determination shall be conclusive and
shall be described in a written statement delivered to the Registered Holders of
the Debentures at their respective Payment Addresses) shall determine the
allocation of the adjusted conversion price between or among shares of such
classes of capital stock.

         (ii) No adjustment in the conversion price shall be required unless
such adjustment would require an increase or decrease of at least two percent
(2%) in such price; provided, however, that any adjustments which by reason of
this subparagraph (e)(ii) of this Article 3 are not required to be made shall be
carried forward and taken into account in any subsequent adjustment. All
adjustments under this Article 3 shall be made to the nearest whole share.
Anything in this Article 3 to the contrary notwithstanding, the Company shall be
entitled to make such reductions in the conversion price, in addition to those
required by this Article 3, as it in its discretion shall determine to be
advisable in order that any stock dividends, subdivision of shares, distribution
of rights to purchase stock or securities, or distribution of securities
convertible into or exchangeable for stock hereafter made by the Company to its
stock holders shall not be taxable.

         (iii) Whenever the conversion price is adjusted as herein provided, the
Company shall promptly deliver to the holders of the Debentures at their
respective Payment Addresses, a certificate certified by the Company's principal
financial and/or accounting officer setting forth: (1) the conversion price
after such adjustment; (2) a brief statement of the facts requiring such
adjustment; and (3) the date such adjustment becomes effective.

(f) Reclassification, Reorganization or Merger.  In case of any
reclassification, capital reorganization or other change of outstanding shares
of Common Stock of the Company, or in case

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of any consolidation or merger of the Company with or into another corporation
(other than a merger with a subsidiary in which merger the Company is the
continuing corporation and which does not result in any reclassification,
capital reorganization or other change of outstanding shares of Common Stock or
the class issuable upon conversion of this Debenture) or in case of any sale,
lease or conveyance to another corporation of the property of the Company as an
entirety, the Company shall, as a condition precedent to such transaction, cause
effective provisions to be made so that the holder of this Debenture shall have
the right thereafter by converting this Debenture, to acquire the kind and
amount of shares of stock and other securities and property receivable upon such
event by a holder of the number of shares of Common Stock which might have been
acquired upon conversion of this Debenture immediately prior to such event. Any
such provision shall include provision for adjustments which shall be as nearly
equivalent as may be practicable to the adjustments provided for in this
Debenture.

                                   ARTICLE 4

                 Registration under the Securities Act of 1933.

(a) Piggyback Registration Rights. During the period commencing as of the date
hereof through May 31, 1999, the Company shall advise the Registered Holder of
this Debenture or the Debenture Shares or any then holder of the Debenture or
Debenture Shares (such persons being collectively referred to herein as
"holders") by written notice at least two weeks prior to the filing of any
registration statement under the Act (other than a registration statement on
Form S-4, Form S-8 or subsequent similar forms) that the Company intends to file
a registration statement covering securities of the Company and will upon the
request of any such holder, include in any such registration statement such
information as may be required to permit a public offering of the Debenture
Shares; provided, however, that if the registration statement relates to a
public offering by the Company of its securities and any managing underwriter
advises the Company that it believes the inclusion in the offering of securities
being sold by the holder would adversely affect the ability of the Company to
complete the public offering, then the holder will agree to reduce the number of
Debenture Shares to be registered to a number of shares which, when aggregated
with all other Debenture Shares (with such reductions to be made pro rata by
Debenture Shareholders) shall be not less than ten percent (10%) of the number
of shares being offered by the Company and the holder will further agree not to
make any sales of the securities so included for a period of ninety (90) days
from the effective date of such registration statement. The Company shall keep
such registration statement current for a period of up to nine (9) months from
the conclusion of such ninety (90) day period; provided, however, that the
Company shall not be required to keep the registration statement effective
beyond the date after which the registration statement must be amended to
include updated audited financial statements. The Company shall supply
prospectuses, qualify the Debenture and the Debenture Shares for sale in such
states as such holder reasonably

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requests and furnish indemnification in the manner as set forth in of this
Article 4. Such holders shall furnish information and indemnification in the
manner set forth in of this Article 4.

(b) Other Provisions Pertaining to Registration Rights.  The following provision
of this Article 4 shall also be applicable:

         (i) Within twenty (20) business days after receiving any such notice
pursuant to paragraph (a) of this Article 4, the Company shall give notice to
the other holders of Debentures and Debenture Shares, advising that the Company
is proceeding with such registration and offering to include therein the
Debenture Shares of such other holders, provided that they shall furnish the
Company with such appropriate information (relating to the intentions of such
holders) in connection therewith as the Company shall request in writing.
Following the effective date of such registration statement, the Company shall,
upon the request of any holder of Debentures and/or Debenture Shares, forthwith
supply such number of prospectuses meeting the requirements of the Act as shall
be requested by such holder to permit such holder to make a public distribution
of all Debenture Shares from time to time offered or sold by such holder,
provided that such holder shall from time to time furnish the Company with such
appropriate information (relating to the intentions of such holder) in
connection therewith as the Company shall request in writing. The Company shall
also use its best efforts to qualify the Debenture Shares for sale in such
states as the holders shall reasonably request.

         (ii) The Company shall bear the entire cost and expense of any
registration of securities initiated by it under paragraphs (a) and (b) of this
Article 4. Any holder whose Debenture Shares are included in any such
registration statement pursuant to this Article 4 shall, however, bear the fees
of his own counsel and accountants and any transfer taxes or underwriting
discounts or commissions applicable to the Debenture Shares sold by him pursuant
thereto.

         (iii) The Company shall indemnify and hold harmless each such holder
from and against any and any losses, claims, damages and liabilities caused by
any untrue statement or alleged untrue statement of a material fact contained in
the Registration Statement or any post-effective amendment thereto or any
registration statement under the Act or any prospectus included therein required
to be filed or furnished by reason of this Article 4 or any application or other
filing under any state securities law caused by any omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not misleading to which such holder may become subject under the Act,
the Securities Exchange Act of 1934, as amended, or other Federal or state
statutory law or regulation, at common law or otherwise, except insofar as such
losses, claims, damages or liabilities are caused by any such untrue statement
or omission which is based upon information furnished or required to be
furnished to the Company by any such holder or any underwriter expressly for use
therein; provided, however, that any such holder shall at the same time
indemnify the Company, its directors, each officer signing the related
registration statement, each person, if any, who controls the Company within the
meaning of such Act and each other Holder,

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from and against any and all losses, claims, damages and liabilities caused by
any untrue statement of a material fact contained in any registration statement
or any prospectus required to be filed or furnished by reason of this Article 4
or caused by any omission to state therein a material fact required to be stated
therein or necessary to make the statements therein not misleading, insofar as
such losses, claims, damages or liabilities are caused by any untrue statement
or omission is based upon information furnished to the Company by any such
holder expressly for use therein.

         (iv) Neither the giving of any notice by any such majority holder nor
the making of any request for prospectuses shall impose any upon such majority
holder or owner making such request any obligation to sell any Debentures or
Debenture Shares, or exercise any Debentures.

(c) Continuing Nature of Obligation.  The Company's agreements with respect to
the Debentures or Debenture Shares in this Article 4 shall continue in effect
regardless of the conversion and surrender of this Debenture.


                                   ARTICLE 5

                                 Miscellaneous

(a) Notice to Company. Notice shall be given to the Company by certified mail,
return receipt requested. Notices to the Company shall be addressed to UNSI
Corporation, c/o Forstmann-Leff Associates, Inc, 55 East 52nd Street, New York,
New York 10055, Attention: Peter A. Lusk, Chairman of the Board, or such other
address as the Company may, from time to time advise the Registered Holders.
Notices to Registered Holders shall be addressed to their respective Payment
Addresses and shall be given by certified mail, return receipt requested.
Notices shall be deemed given on the date mailed.

(b) Governing Law.  This Debenture shall be governed by the laws of the State of
New York applicable to agreements executed and to be performed wholly within
such state.

(c) Rights of Debenture Holder. Nothing in this Debenture shall be construed to
modify, amend or limit in any way the right of any holder of this Debenture to
bring an action against the Company in the event the Company fails to pay
principal of and interest on this Debenture when due, and if the holder of this
Debenture shall be required to commence a legal proceeding to enforce payment of
this Debenture, the Company shall pay the holder's reasonable legal fees and
expenses.

(d) Register. The Company shall keep at its principal office a register in which
the Company maintains a list of names and addresses of the holders of the
Debentures, (and any subsequent transfer or assignment) (the "Payment
Addresses")and shall provide for the registration of transfer of Debentures.
Until otherwise advised by the Registered Holder of this Debenture in accordance

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with paragraph (a) of this Article 5, the Company may treat the person in whose
name this Debenture is registered as the Registered Holder of such Debenture for
the purpose of receiving payment of principal and interest on such Debenture,
and for all other purposes relating to this Debenture.


                                             UNSI CORPORATION


                                             By:
                                                ------------------------------
                                                Peter A. Lusk, Chairman of the
                                                Board of Directors



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                              NOTICE OF CONVERSION


                       [To be Signed Only Upon Conversion
                         of Part or All of Debentures]


                                UNSI CORPORATION


                                            The undersigned, the holder of the
foregoing Debenture, hereby surrenders such Debenture for conversion into shares
of Common Stock of UNSI CORPORATION to the extent of $_____________ * unpaid
principal amount of due on such Debenture, and requests that the certificates
for such shares be issued in the name of __________________, and delivered to
__________________, whose address is ___________________.



DATED:



-----------------------------------------
                                               (Signature)

                                              (Signature must conform in all
respects to name of holder as specified on the face of the Debenture.)


*        Insert here the unpaid principal amount of the Debenture (or, in the
         case of a partial conversion, the portion thereof as to which the
         Debenture is being converted). In the case of a partial conversion, a
         new Debenture will be issued and delivered, representing the
         unconverted portion of the unpaid principal amount of this Debenture,
         to or upon the order of the holder surrendering such Debenture.


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