AMENDED AND RESTATED
UNCONDITIONAL CONTINUING GUARANTY

THIS AMENDED AND RESTATED UNCONDITIONAL CONTINUING GUARANTY (“Guaranty”) is
executed as of January 23, 2008, by DETENTION CONTRACTING GROUP, LTD., a Texas
limited partnership, ISI DETENTION CONTRACTING GROUP, INC., a Texas corporation,
ISI DETENTION CONTRACTING GROUP, INC., a California corporation, ISI DETENTION
CONTRACTING GROUP, INC., a New Mexico corporation, ISI DETENTION SYSTEMS, INC.,
a Texas corporation, ISI SYSTEMS, LTD., a Texas limited partnership, METROPLEX
CONTROL SYSTEMS, INC., a Texas corporation, ISI CONTROLS, LTD., a Texas limited
partnership, METROPLEX COMMERCIAL FIRE AND SECURITY ALARMS, INC., a Texas
corporation and MCFSA, LTD., a Texas limited partnership (collectively,
“Guarantor”), for the benefit of LASALLE BANK NATIONAL ASSOCIATION (“Bank”).
 
RECITALS

A. On October 21, 2004, Guarantor executed and delivered to Bank a Continuing
Unconditional Guaranty (“Original Guaranty”) pertaining to the Bank’s loans and
financial accommodations to ISI Detention Contracting, Inc., a Delaware
corporation (n/k/a ISI Security Group, Inc.).
 
B.  ISI Security Group, Inc., a Delaware corporation (“Borrower”) and Bank have
entered into that certain Amended and Restated Loan and Security Agreement of
even date herewith (the “Loan Agreement”), pursuant to which the Bank has agreed
to make a revolving loan and a term loan in the original aggregate amount of
SIXTEEN MILLION TWO HUNDRED AND FIFTY THOUSAND AND NO/100 DOLLARS
($16,250,000.00) (the “Loans”). All capitalized terms used herein but not
defined herein shall have the meanings ascribed to them in the Loan Agreement.
 
B. The Bank is not willing to make the Loans, or otherwise extend credit, to
Borrower unless Guarantor unconditionally guarantees payment and performance to
Bank of the Obligations; and
 
C. Guarantor is a subsidiary of Borrower, and Guarantor will directly benefit
from the Bank making the Loans to Borrower.
 
AGREEMENT

NOW, THEREFORE, as an inducement to the Bank to make the Loans to Borrower, and
for other good and valuable consideration, the receipt and legal sufficiency of
which are hereby acknowledged, Guarantor agrees with Bank, as follows:
 

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Section 1. Guaranty of Obligations. 

Guarantor hereby absolutely, irrevocably and unconditionally guarantees to Bank
the payment and performance of the Obligations as and when the same shall be due
and payable, whether by lapse of time, by acceleration of maturity or otherwise.
Guarantor hereby absolutely, irrevocably and unconditionally covenants and
agrees that it is liable, jointly and severally, for the Obligations as a
primary obligor, and that Guarantor shall fully perform each and every term and
provision hereof. This Guaranty is a guaranty of payment and not of collection
only. Bank shall not be required to exhaust any right or remedy or take any
action against Borrower or any other person or entity or any collateral.
Guarantor agrees that, as between Guarantor and Bank, the Obligations may be
declared to be due and payable for the purposes of this Guaranty notwithstanding
any stay, injunction or other prohibition which may prevent, delay or vitiate
any declaration as regards Borrower and that in the event of a declaration or
attempted declaration, the Obligations shall immediately become due and payable
by Guarantor for the purposes of this Guaranty.

Section 2. Guaranty Absolute. Guarantor guarantees that the Obligations shall be
paid strictly in accordance with the terms of the Loan Documents. The liability
of Guarantor under this Guaranty is absolute and unconditional irrespective of:
(a) any change in the time, manner or place of payment of, or in any other term
of, all or any of the Obligations, or any other amendment or waiver of or any
consent to departure from any of the terms of any Loan Document, including any
increase or decrease in the rate of interest thereon; (b) any release or
amendment or waiver of, or consent to departure from, or failure to act by Bank
with respect to, any other guaranty or support document, or any exchange,
release or non-perfection of, or failure to act by Bank with respect to, any
Collateral, for all or any of the Obligations; (c) any present or future law,
regulation or order of any jurisdiction (whether of right or in fact) or of any
agency thereof purporting to reduce, amend, restructure or otherwise affect any
term of the Obligations or any Loan Document; (d) any change in the corporate
existence, structure, or ownership of Borrower; (e) without being limited by the
foregoing, any lack of validity or enforceability of any Loan Document; and (f)
any other setoff, recoupment, defense or counterclaim whatsoever (in any case,
whether based on contract, tort or any other theory) with respect to the Loan
Documents or the transactions contemplated thereby which might constitute a
legal or equitable defense available to, or discharge of, Borrower or a
Guarantor.

Section 3. Guaranty Irrevocable. This Guaranty is a continuing guaranty of the
payment of all Obligations now or hereafter existing and shall remain in full
force and effect until payment in full of all Obligations and other amounts
payable under this Guaranty and until the Loan Documents are no longer in
effect.

Section 4. Reinstatement. This Guaranty shall continue to be effective or be
reinstated, as the case may be, if at any time any payment of any of the
Obligations is rescinded or must otherwise be returned by the Bank on the
insolvency, bankruptcy or reorganization of Borrower or otherwise, all as though
the payment had not been made, whether or not Bank is in possession of the
Guaranty.

Section 5. Subrogation. Guarantor shall not exercise any rights which it may
acquire by way of subrogation, by any payment made under this Guaranty or
otherwise, until all the Obligations have been paid in full and the Loan
Documents are no longer in effect. If any amount is paid to Guarantor on account
of subrogation rights under this Guaranty at any time when all the Obligations
have not been paid in full, the amount shall be held in trust for the benefit of
the Bank and shall be promptly paid to Bank to be credited and applied to the
Obligations, whether matured or unmatured or absolute or contingent, in
accordance with the terms of the Loan Documents. If Guarantor makes payment to
Bank of all or any part of the Obligations and all the Obligations are paid in
full and the Loan Documents are no longer in effect, Bank shall, at Guarantor's
request, execute and deliver to Guarantor appropriate documents, without
recourse and without representation or warranty, necessary to evidence the
transfer by subrogation to Guarantor of the interest in the Obligations
resulting from the payment.
 
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Section 6. Subordination. Without limiting Bank’s rights under any other
agreement, any liabilities owed by Borrower to Guarantor in connection with any
extension of credit or financial accommodation by Guarantor to or for the
account of Borrower, including but not limited to interest accruing at the
agreed contract rate after the commencement of a bankruptcy or similar
proceeding, are hereby subordinated to the Obligations, and such liabilities of
Borrower to Guarantor, if Bank so requests, shall be collected, enforced and
received by Guarantor as trustee for the Bank and shall be paid over to Bank on
account of the Obligations but without reducing or affecting in any manner the
liability of Guarantor under the other provisions of this Guaranty.

Section 7. Representations and Warranties. Guarantor represents and warrants
that: (a) this Guaranty (i) has been authorized by all necessary action; (ii)
does not violate any agreement, instrument, law, regulation or order applicable
to Guarantor; (iii) does not require the consent or approval of any person or
entity, including but not limited to any governmental authority, or any filing
or registration of any kind; and (iv) is the legal, valid and binding obligation
of Guarantor enforceable against Guarantor in accordance with its terms, except
to the extent that enforcement may be limited by applicable bankruptcy,
insolvency and other similar laws affecting creditors' rights generally; and (b)
in executing and delivering this Guaranty, Guarantor has (i) without reliance on
Bank or any information received from Bank and based upon such documents and
information it deems appropriate, made an independent investigation of the
transactions contemplated hereby and Borrower, Borrower’s business, assets,
operations, prospects and condition, financial or otherwise, and any
circumstances which may bear upon such transactions, Borrower or the obligations
and risks undertaken herein with respect to the Obligations; (ii) adequate means
to obtain from Borrower on a continuing basis information concerning Borrower;
(iii) full and complete access to the Loan Documents and any other documents
executed in connection with the Loan Documents; and (iv) not relied and will not
rely upon any representations or warranties of Bank not embodied herein or any
acts heretofore or hereafter taken by Bank (including but not limited to any
review by Bank of the affairs of Borrower).

Section 8. Financial Reports and Covenants.

(a)  Guarantor shall keep adequate books and records of account in accordance
with methods acceptable to Bank, consistently applied and furnish to Bank the
financial statements described in the Loan Agreement.
 
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(b)  Bank and its accountants shall have the right to examine the records,
books, management and other papers of Guarantor which reflect upon its financial
condition, at the Collateral or at any office regularly maintained by Guarantor
where the books and records are located. Bank and its accountants shall have the
right to make copies and extracts from the foregoing records and other papers.
In addition, Bank and its accountants shall have the right to examine and audit
the books and records of Guarantor pertaining to the income, expenses and
operation of the Collateral during reasonable business hours at any office of
Guarantor where the books and records are located.
 
Section 9. Remedies Generally. The remedies provided in this Guaranty are
cumulative and not exclusive of any remedies provided by law.

Section 10. Setoff. If a Default shall have occurred and be continuing, Bank is
hereby authorized at any time and from time to time, to the fullest extent
permitted by law, and to the extent permitted under the Loan Agreement, to set
off and apply any and all deposits (general or special, time or demand,
provisional or final) at any time held and other obligations at any time owing
by Borrower to or for the credit or the account of Guarantor against any of and
all the Obligations held by Bank, irrespective of whether or Bank shall have
made any demand under this Guaranty and although such Obligations may be
unmatured. The rights of Bank under this Section are in addition to other rights
and remedies (including other rights of setoff) which Bank may have.

Section 11. Formalities. Guarantor waives presentment, demand, notice of
dishonor, protest, notice of acceptance of this Guaranty or incurrence of any of
the Obligations and any other formality with respect to any of the Obligations
or this Guaranty.

Section 12. Amendments and Waivers. No amendment or waiver of any provision of
this Guaranty, nor consent to any departure by Guarantor therefrom, shall be
effective unless it is in writing and signed by Bank, and then the waiver or
consent shall be effective only in the specific instance and for the specific
purpose for which given. No failure on the part of Bank to exercise, and no
delay in exercising, any right under this Guaranty shall operate as a waiver or
preclude any other or further exercise thereof or the exercise of any other
right.

Section 13. Expenses. Guarantor shall reimburse Bank on demand for all costs,
expenses and charges (including without limitation fees and charges of external
legal counsel for Bank and costs allocated by its internal legal department)
incurred by Bank in connection with the performance or enforcement of this
Guaranty. The obligations of Guarantor under this Section shall survive the
termination of this Guaranty.

Section 14. Assignment. This Guaranty shall be binding on, and shall inure to
the benefit of Guarantor and Bank and their respective successors and assigns;
provided that Guarantor may not assign or transfer its rights or obligations
under this Guaranty. Without limiting the generality of the foregoing: (a) the
obligations of Guarantor under this Guaranty shall continue in full force and
effect and shall be binding on any successor partnership and on previous
partners and their respective estates if Guarantor is a partnership, regardless
of any change in the partnership as a result of death, retirement or otherwise;
and (b) Bank may assign, sell participations in or otherwise transfer its rights
under the Loan Documents to any other person or entity in accordance with the
terms of the Loan Agreement, and the other person or entity shall then become
vested with all the rights granted to Bank, as applicable, in this Guaranty or
otherwise.
 
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Section 15. Captions. The headings and captions in this Guaranty are for
convenience only and shall not affect the interpretation or construction of this
Guaranty.

Section 16. Notices. All notices or other written communications hereunder shall
be in writing and shall be delivered by hand or overnight courier service,
mailed by certified or registered mail or sent by telecopy, as follows:

To the Guarantor:
ISI Security Group, Inc.
12903 Delivery Drive
San Antonio, Texas 78247
Attention: Sam Youngblood
   
With a copy to:
Kilpatrick & Lockhart Preston Gates Ellis LLP
111 Congress Avenue, Suite 900
Austin, Texas 78701
Attention: Hull Youngblood, Esq.
   
To the Lender:
LaSalle Bank National Association
135 South LaSalle Street
Chicago, Illinois 60603
Attention: Commercial Lending Division
   
With copy to:
Sherman & Howard L.L.C.
633 17th Street, Suite 3000
Denver, Colorado 80202
Attention: Alan M. Keeffe, Esq,

Guarantor and Bank may change its address or telecopy number for notices and
other communications hereunder by notice to the other party. All notices and
other communications given to Guarantor or Bank in accordance with the
provisions of this Guaranty shall be deemed to have been given on the date of
receipt.

Section 17. Governing Law; Jurisdiction; Consent to Service of Process.

(a) This Guaranty shall be construed in accordance with and governed by the law
of the State of Illinois.
 
(b) Guarantor hereby irrevocably and unconditionally submits, for itself and its
property, to the nonexclusive jurisdiction of any United States Federal or
Illinois State court sitting in Chicago, Illinois, and any appellate court from
any thereof, in any action or proceeding arising out of or relating to this
Guaranty, or for recognition or enforcement of any judgment, and Guarantor
hereby irrevocably and unconditionally agrees that all claims in respect of any
such action or proceeding may be heard and determined in such Illinois State or,
to the extent permitted by law, in such Federal court. Guarantor hereto agrees
that a final judgment in any such action or proceeding shall be conclusive and
may be enforced in other jurisdictions by suit on the judgment or in any other
manner provided by law. Nothing in this Guaranty shall affect any right that
Bank may otherwise have to bring any action or proceeding relating to this
Guaranty against Guarantor or its properties in the courts of any jurisdiction.
 
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(c) Guarantor hereby irrevocably and unconditionally waives, to the fullest
extent it may legally and effectively do so, any objection which it may now or
hereafter have to the laying of venue of any suit, action or proceeding arising
out of or relating to this Guaranty in any court referred to in subsection (b)
above. Guarantor hereby irrevocably waives, to the fullest extent permitted by
law, the defense of an inconvenient forum to the maintenance of such action or
proceeding in any such court.
 
(d) Guarantor irrevocably consents to service of process in the manner provided
for notices in Section 16 hereof. Nothing in this Guaranty will affect the right
of Bank to serve process in any other manner permitted by law.
 
Section 18. Invalid Provisions. If any provision of this Guaranty is held to be
illegal, invalid, or unenforceable under present or future laws effective during
the term of this Guaranty, such provision shall be fully severable and this
Guaranty shall be construed and enforced as if such illegal, invalid or
unenforceable provision had never comprised a part of this Guaranty, and the
remaining provisions of this Guaranty shall remain in full force and effect and
shall not be affected by the illegal, invalid or unenforceable provision or by
its severance from this Guaranty, unless such continued effectiveness of this
Guaranty, as modified, would be contrary to the basic understandings and
intentions of the parties as expressed herein.
 
Section 19. ENTIRETY. THIS GUARANTY AND THE OTHER LOAN DOCUMENTS EXECUTED BY
GUARANTOR EMBODY THE FINAL, ENTIRE AGREEMENT OF GUARANTOR AND BANK WITH RESPECT
TO THE SUBJECT MATTER HEREOF AND THEREOF AND SUPERSEDES ANY AND ALL PRIOR
COMMITMENTS, AGREEMENTS, REPRESENTATIONS, AND UNDERSTANDINGS, WHETHER WRITTEN OR
ORAL, RELATING TO THE SUBJECT MATTER HEREOF AND THEREOF. THIS GUARANTY AND THE
OTHER LOAN DOCUMENTS EXECUTED BY GUARANTOR ARE INTENDED BY GUARANTOR AND BANK AS
A FINAL AND COMPLETE EXPRESSION OF THE TERMS HEREOF AND THEREOF, AND NO COURSE
OF DEALING AMONG GUARANTOR AND BANK, NO COURSE OF PERFORMANCE, NO TRADE
PRACTICES, AND NO EVIDENCE OF PRIOR, CONTEMPORANEOUS OR SUBSEQUENT ORAL
AGREEMENTS OR DISCUSSIONS OR OTHER EXTRINSIC EVIDENCE OF ANY NATURE SHALL BE
USED TO CONTRADICT, VARY, SUPPLEMENT OR MODIFY ANY TERM OF THIS GUARANTY OR ANY
OTHER LOAN DOCUMENT EXECUTED BY GUARANTOR. THERE ARE NO ORAL AGREEMENTS BETWEEN
GUARANTOR AND BANK.
 
Section 20. WAIVER OF RIGHT TO TRIAL BY JURY. GUARANTOR AND BANK EACH HEREBY
WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE
TO A TRIAL BY JURY IN ANY LEGAL PROCEEDING DIRECTLY OR INDIRECTLY ARISING OUT OF
OR RELATING TO THIS GUARANTY OR THE TRANSACTIONS CONTEMPLATED HEREBY (WHETHER
BASED ON CONTRACT, TORT OR ANY OTHER THEORY). GUARANTOR AND BANK EACH
(A) CERTIFIES THAT NO REPRESENTATIVE, AGENT OR ATTORNEY OF THE OTHER PARTY HAS
REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE
EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER AND (B) ACKNOWLEDGES
THAT IT AND SUCH OTHER PARTY HAVE BEEN INDUCED TO EXECUTE OR ACCEPT THIS
GUARANTY BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS
SECTION 20.
 
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Section 21. AMENDMENT. This Guaranty amends and restates the Original Guaranty
in its entirety.
 
[SIGNATURE PAGES FOLLOW]

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IN WITNESS WHEREOF, Guarantor has caused this Guaranty to be duly executed and
delivered by its duly authorized officer as of the date first above written.

DETENTION CONTRACTING GROUP, LTD.,
a Texas limited partnership
 
By:
ISI DETENTION CONTRACTING GROUP, INC.,
 
a Texas corporation, its general partner
 
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
 
ISI DETENTION CONTRACTING GROUP, INC., a
Texas corporation
 
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
 
ISI DETENTION CONTRACTING GROUP, INC., a
California corporation
 
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
 
ISI DETENTION CONTRACTING GROUP, INC.,
a New Mexico corporation
 
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
 
ISI DETENTION SYSTEMS, INC.,
a Texas corporation
 
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO

 
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ISI SYSTEMS, LTD.,
a Texas limited partnership
   
By:
ISI DETENTION SYSTEMS, INC.,
 
a Texas corporation, its general partner
   
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
   
METROPLEX CONTROL SYSTEMS, INC.,
a Texas corporation (f/k/a ISI Metroplex Controls, Inc.)
   
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
   
ISI CONTROLS, LTD.,
a Texas limited partnership
   
By:
METROPLEX CONTROL SYSTEMS, INC.,
 
a Texas corporation, its general partner
   
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
   
METROPLEX COMMERCIAL FIRE AND
SECURITY ALARMS, INC.,
a Texas corporation
   
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO
   
MCFSA, LTD.,
a Texas limited partnership
   
By:
METROPLEX COMMERCIAL FIRE AND
 
SECURITY ALARMS, INC.,
 
a Texas corporation, its general partner
   
By:
/s/ Sam Youngblood
Name: Sam Youngblood
Title: CEO

 
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