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                                    EXHIBIT K

                                    GUARANTY


         THIS GUARANTY dated as of September 25, 1996 is executed in favor of
HARRIS TRUST AND SAVINGS BANK, as Agent, and the Banks which are parties to the
Credit Agreement referred to below.

                              W I T N E S S E T H:

         WHEREAS, Gibraltar Packaging Group, Inc. (the "Company") has entered
into a Credit Agreement dated as of even date herewith (as amended or otherwise
modified from time to time, the "Credit Agreement") with certain financial
institutions (collectively the "Banks" and individually each a "Bank") and
Harris Trust and Savings Bank, as agent (in its capacity as agent, the "Agent"),
pursuant to which the Banks have agreed to make loans to, and issue (or purchase
participations in) letters of credit for the account of, the Company;

         WHEREAS, the operations of each of the undersigned are integrated with
those of the Company to such an extent that the financial strength and
flexibility of the Company have a direct impact on each of the undersigned; and

         WHEREAS, each of the undersigned will benefit from the making of loans
and the issuance of letters of credit pursuant to the Credit Agreement and is
willing to guaranty the Liabilities (as defined below) as hereinafter set forth;

         NOW, THEREFORE, for good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, each of the undersigned hereby
jointly and severally unconditionally, as primary obligor and not merely as
surety, guarantees the full and prompt payment when due, whether by acceleration
or otherwise, and at all times thereafter, of all obligations (monetary or
otherwise) of the Company to each of the Banks and the Agent, howsoever created,
arising or evidenced, whether direct or indirect, absolute or contingent, now or
hereafter existing, or due or to become due, which arise out of or in connection
with the Credit Agreement, the Notes (as defined in the Credit Agreement), any
other Loan Document (as defined in the Credit Agreement) or any document or
instrument (including any Hedging Agreement (as defined in the Credit Agreement)
entered into with any Bank or any affiliate thereof) executed in connection
therewith, in each case as the same may be amended, modified, extended or
renewed from time to time (all such obligations being herein collectively called
the "Liabilities"); provided, however, that the liability of each of the
undersigned hereunder shall be limited to the maximum amount of the Liabilities
which such undersigned may guaranty without violating any fraudulent conveyance
or fraudulent transfer law (plus all costs and expenses paid or incurred by the
Agent or any Bank in enforcing 


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this Guaranty against such undersigned).


         Each of the undersigned agrees that, in the event of the dissolution or
insolvency of the Company or any undersigned, or the inability or failure of the
Company or any undersigned to pay debts as they become due, or an assignment by
the Company or any undersigned for the benefit of creditors, or the occurrence
of any other Event of Default (as defined in the Credit Agreement) under Section
12.1.4 of the Credit Agreement, and if such event shall occur at a time when any
of the Liabilities may not then be due and payable, such undersigned will pay to
the Agent for the account of the Banks forthwith the full amount which would be
payable hereunder by such undersigned if all Liabilities were then due and
payable.

         To secure all obligations of each of the undersigned hereunder, the
Agent and each Bank shall have a lien on and security interest in (and may,
without demand or notice of any kind, at any time and from time to time when any
amount shall be due and payable by such undersigned hereunder, appropriate and
apply toward the payment of such amount, in such order of application as the
Agent or the Banks may elect) any and all balances, credits, deposits, accounts
or moneys of or in the name of such undersigned now or hereafter with the Agent
or such Bank and any and all property of every kind or description of or in the
name of such undersigned now or hereafter, for any reason or purpose whatsoever,
in the possession or control of, or in transit to, the Agent or such Bank or any
agent or bailee for the Agent or such Bank.

         This Guaranty shall in all respects be a continuing, absolute and
unconditional guaranty, and shall remain in full force and effect
(notwithstanding, without limitation, the dissolution of any of the undersigned
or that at any time or from time to time no Liabilities are outstanding) until
all Commitments (as defined in the Credit Agreement) have terminated and all
Liabilities have been paid in full.

         The undersigned further agree that if at any time all or any part of
any payment theretofore applied by the Agent or any Bank to any of the
Liabilities is or must be rescinded or returned by the Agent or such Bank for
any reason whatsoever (including, without limitation, the insolvency, bankruptcy
or reorganization of the Company or any of the undersigned), such Liabilities
shall, for the purposes of this Guaranty, to the extent that such payment is or
must be rescinded or returned, be deemed to have continued in existence,
notwithstanding such application by the Agent or such Bank, and this Guaranty
shall continue to be effective or be reinstated, as the case may be, as to such
Liabilities, all as though such application by the Agent or such Bank had not
been made.

         The Agent or any Bank may, from time to time, at its sole 


                                      -2-

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discretion and without notice to the undersigned  (or any of them),  take any or
all of the following  actions:  (a) retain or obtain a security  interest in any
property  to secure any of the  Liabilities  or any  obligation  hereunder,  (b)
retain or obtain the primary or secondary obligation of any obligor or obligors,
in addition to the  undersigned,  with  respect to any of the  Liabilities,  (c)
extend or renew any of the Liabilities  for one or more periods  (whether or not
longer than the original period),  alter or exchange any of the Liabilities,  or
release or compromise any obligation of any of the undersigned  hereunder or any
obligation  of any  nature  of any  other  obligor  with  respect  to any of the
Liabilities,  (d) release its  security  interest in, or  surrender,  release or
permit  any  substitution  or  exchange  for,  all or any  part of any  property
securing any of the Liabilities or any obligation hereunder,  or extend or renew
for one or more  periods  (whether  or not longer than the  original  period) or
release,  compromise,  alter or exchange  any  obligations  of any nature of any
obligor with respect to any such property, and (e) resort to the undersigned (or
any of them) for payment of any of the Liabilities  when due, whether or not the
Agent or such Bank shall  have  resorted  to any  property  securing  any of the
Liabilities  or any  obligation  hereunder or shall have  proceeded  against any
other of the undersigned or any other obligor primarily or secondarily obligated
with respect to any of the Liabilities.

         Any amounts received by the Agent or any Bank from whatever source on
account of the Liabilities may be applied by it toward the payment of the
Liabilities; and, notwithstanding any payments made by or for the account of any
of the undersigned pursuant to this Guaranty, the undersigned shall not be
subrogated to any rights of the Agent or any Bank until such time as this
Guaranty shall have been discontinued as to all of the undersigned and the Agent
and the Banks shall have received payment of the full amount of all liabilities
of the undersigned hereunder.

         The undersigned hereby expressly waive: (a) notice of the acceptance by
the Agent or any Bank of this Guaranty, (b) notice of the existence or creation
or non-payment of all or any of the Liabilities, (c) presentment, demand, notice
of dishonor, protest, and all other notices whatsoever, and (d) all diligence in
collection or protection of or realization upon any Liabilities or any security
for or guaranty of any Liabilities.

         Each of the undersigned further agrees to pay all expenses (including
attorneys' fees and legal expenses) paid or incurred by the Agent or any Bank in
endeavoring to collect the Liabilities of such undersigned, or any part thereof,
and in enforcing this Guaranty against such undersigned.

         The creation or existence from time to time of additional Liabilities
to the Agent or the Banks or any of them is hereby 

                                      -3-


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authorized,  without notice to the undersigned (or any of them), and shall in no
way affect or impair the rights of the Agent or the Banks or the  obligations of
the undersigned under this Guaranty.

         The Agent and any Bank may from time to time, without notice to the
undersigned (or any of them), assign or transfer any or all of the Liabilities
or any interest therein; and, notwithstanding any such assignment or transfer or
any subsequent assignment or transfer thereof, such Liabilities shall be and
remain Liabilities for the purposes of this Guaranty, and each and every
immediate and successive assignee or transferee of any of the Liabilities or of
any interest therein shall, to the extent of the interest of such assignee or
transferee in the Liabilities, be entitled to the benefits of this Guaranty to
the same extent as if such assignee or transferee were a Bank.

         No delay on the part of the Agent or any Bank in the exercise of any
right or remedy shall operate as a waiver thereof, and no single or partial
exercise by the Agent or any Bank of any right or remedy shall preclude other or
further exercise thereof or the exercise of any other right or remedy; nor shall
any modification or waiver of any provision of this Guaranty be binding upon the
Agent or the Banks except as expressly set forth in a writing duly signed and
delivered on behalf of the Agent. No action of the Agent or any Bank permitted
hereunder shall in any way affect or impair the rights of the Agent or any Bank
or the obligations of the undersigned under this Guaranty. For purposes of this
Guaranty, Liabilities shall include all obligations of the Company to the Agent
or any Bank arising under or in connection with the Credit Agreement, any Note
or any other Loan Document, notwithstanding any right or power of the Company or
anyone else to assert any claim or defense as to the invalidity or
unenforceability of any obligation, and no such claim or defense shall affect or
impair the obligations of the undersigned hereunder.

         Pursuant to the Credit Agreement, (a) this Guaranty has been delivered
to the Agent and (b) the Agent has been authorized to enforce this Guaranty on
behalf of itself and each of the Banks. All payments by the undersigned pursuant
to this Guaranty shall be made to the Agent for the ratable benefit of the
Banks.

         This Guaranty shall be binding upon the undersigned and the successors
and assigns of the undersigned; and to the extent that the Company or any of the
undersigned is either a partnership or a corporation, all references herein to
the Company and to the undersigned, respectively, shall be deemed to include any
successor or successors, whether immediate or remote, to such partnership or
corporation. The term "undersigned" as used herein shall mean all parties
executing this Guaranty and each of them, and all such parties shall be jointly
and severally 

                                      -4-


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obligated hereunder.

         This Guaranty has been delivered at Chicago, Illinois, and shall be
construed in accordance with and governed by the internal laws of the State of
Illinois. Wherever possible each provision of this Guaranty shall be interpreted
in such manner as to be effective and valid under applicable law, but if any
provision of this Guaranty shall be prohibited by or invalid under such law,
such provision shall be ineffective to the extent of such prohibition or
invalidity, without invalidating the remainder of such provision or the
remaining provisions of this Guaranty.

         This Guaranty may be executed in any number of counterparts and by the
different parties hereto on separate counterparts, and each such counterpart
shall be deemed to be an original but all such counterparts shall together
constitute one and the same Guaranty as if only one original had been executed.
At any time after the date of this Guaranty, one or more additional persons or
entities may become parties hereto by executing and delivering to the Agent a
counterpart of this Guaranty. Immediately upon such execution and delivery (and
without any further action), each such additional person or entity will become a
party to, and will be bound by all of the terms of, this Guaranty.

         ANY LITIGATION BASED HEREON, OR ARISING OUT OF, UNDER OR IN CONNECTION
WITH THIS GUARANTY OR ANY OTHER LOAN DOCUMENT, SHALL BE BROUGHT AND MAINTAINED
EXCLUSIVELY IN THE COURTS OF THE STATE OF ILLINOIS OR IN THE UNITED STATES
DISTRICT COURT FOR THE NORTHERN DISTRICT OF ILLINOIS; PROVIDED, HOWEVER, THAT
ANY SUIT SEEKING ENFORCEMENT AGAINST ANY COLLATERAL OR OTHER PROPERTY MAY BE
BROUGHT, AT THE AGENT'S OPTION, IN THE COURTS OF ANY JURISDICTION WHERE SUCH
COLLATERAL OR OTHER PROPERTY MAY BE FOUND. EACH OF THE UNDERSIGNED HEREBY
EXPRESSLY AND IRREVOCABLY SUBMITS TO THE JURISDICTION OF THE COURTS OF THE STATE
OF ILLINOIS AND OF THE UNITED STATES DISTRICT COURT FOR THE NORTHERN DISTRICT OF
ILLINOIS FOR THE PURPOSE OF ANY SUCH LITIGATION AS SET FORTH ABOVE. EACH OF THE
UNDERSIGNED FURTHER IRREVOCABLY CONSENTS TO THE SERVICE OF PROCESS BY REGISTERED
MAIL, POSTAGE PREPAID, TO THE ADDRESS SET FORTH OPPOSITE ITS SIGNATURE HERETO
(OR SUCH OTHER ADDRESS AS IT SHALL HAVE SPECIFIED IN WRITING TO THE AGENT AS ITS
ADDRESS FOR NOTICES HEREUNDER) OR BY PERSONAL SERVICE WITHIN OR WITHOUT THE
STATE OF ILLINOIS. EACH OF THE UNDERSIGNED HEREBY EXPRESSLY AND IRREVOCABLY
WAIVES, TO THE FULLEST EXTENT PERMITTED BY LAW, ANY OBJECTION WHICH IT MAY NOW
OR HEREAFTER HAVE TO THE LAYING OF VENUE OF ANY SUCH LITIGATION BROUGHT IN ANY
SUCH COURT REFERRED TO ABOVE AND ANY CLAIM THAT ANY SUCH LITIGATION HAS BEEN
BROUGHT IN AN INCONVENIENT FORUM. TO THE EXTENT THAT ANY OF THE UNDERSIGNED HAS
OR HEREAFTER MAY ACQUIRE ANY IMMUNITY FROM JURISDICTION OF ANY COURT OF FROM ANY
LEGAL PROCESS (WHETHER THROUGH SERVICE OR NOTICE, ATTACHMENT PRIOR TO JUDGMENT,
ATTACHMENT IN AID OF EXECUTION OR OTHERWISE) 


                                      -5-


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WITH RESPECT TO ITSELF OR ITS  PROPERTY,  SUCH  UNDERSIGNED  HEREBY  IRREVOCABLY
WAIVES SUCH IMMUNITY IN RESPECT OF ITS  OBLIGATIONS  UNDER THIS GUARANTY AND THE
OTHER LOAN DOCUMENTS.

    EACH OF THE UNDERSIGNED, AND (BY ACCEPTING THE BENEFITS HEREOF) EACH OF THE
AGENT AND EACH BANK, HEREBY WAIVES ANY RIGHT TO A TRIAL BY JURY IN ANY ACTION OR
PROCEEDING TO ENFORCE OR DEFEND ANY RIGHTS UNDER THIS GUARANTY, ANY OTHER LOAN
DOCUMENT AND ANY AMENDMENT, INSTRUMENT, DOCUMENT OR AGREEMENT DELIVERED OR WHICH
MAY IN THE FUTURE BE DELIVERED IN CONNECTION HEREWITH OR THEREWITH OR ARISING
FROM ANY BANKING RELATIONSHIP EXISTING IN CONNECTION WITH ANY OF THE FOREGOING,
AND AGREES THAT ANY SUCH ACTION OR PROCEEDING SHALL BE TRIED BEFORE A COURT AND
NOT BEFORE A JURY.




                                      -6-

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         IN WITNESS WHEREOF, this Guaranty has been duly executed and delivered
as of the day and year first above written.


Address:                           RIDGEPAK CORPORATION
1140 Hayden Street
Ft. Wayne, IN  46803

                                   By:  /s/ W E Rose
                                      Title:  President



Address:                           STANDARD PACKAGING AND PRINTING CO.
HWY 73 West
Mt. Gilead, NC  27306

                                   By:  /s/ W E Rose
                                      Title:  CEO




Address:                           NIEMAND HOLDINGS, INC.
274 Riverside Ave.
Westport, CT  06880

                                   By:  /s/ W E Rose
                                      Title:  President



Address:                           NIEMAND INDUSTRIES, INC.
1410 S. Washington Street
Marion, AL  36756

                                   By:  /s/ W E Rose
                                      Title:  Vice President


Address:                           GB LABELS, INC.
1070 S. Riverview Drive
Burlington, NC  27217

                                   By:  /s/ W E Rose
                                      Title:  Senior Vice President


                                  -7-

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