Exhibit 99.1
April 1, 1998



PROTECTION ONE ALARM MONITORING, INC.
4221 W. John Carpenter Fwy
Irving, TX  75063

Attn:  John W. Hesse


Gentlemen:

         Westar Capital,  Inc.  ("Lender") is pleased to make available a credit
facility to Protection One Alarm Monitoring,  Inc., a Delaware  corporation (the
"Borrower") on the following terms and conditions (terms not defined herein have
the meanings assigned to them on Attachment 1 hereto):

I.       The Commitment:

                           A.  Subject  to the  terms and  conditions  set forth
                  herein,  Lender agrees to make available to Borrower until the
                  Maturity  Date  a  revolving  line  of  credit  providing  for
                  Advances in an aggregate  principal  amount not  exceeding the
                  Commitment at any time. Until the Maturity Date,  Borrower may
                  borrow,  repay and reborrow  Advances  within the  Commitment.
                  This agreement is executed in replacement and substitution for
                  that certain Credit Agreement dated as of November 3, 1993, as
                  amended,  among the Borrower,  Protection One Alarm  Services,
                  Inc. and Heller Financial,  Inc., as agent and as lender,  and
                  certain other lenders.

                           B. Base Rate  Advances and LIBOR  Advances made under
                  this facility shall mature no later than the Maturity Date. No
                  WIBOR  Advance  shall  expire  later  than 90 days  after  the
                  Maturity Date, provided however, that if this agreement is not
                  amended and restated  prior to the Maturity Date to extend the
                  Maturity Date beyond the  expiration  date of any  outstanding
                  Advances,  all  outstanding  Advances as of the Maturity Date,
                  together with accrued interest and fees thereon,  shall be due
                  and payable on the Maturity Date.

         .






                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 2



                           C. Unless  Lender shall  otherwise  agree in writing,
                  net proceeds from any equity offering by Protection One, Inc.,
                  a  Delaware   corporation  and  Borrower's   corporate  parent
                  ("Parent"),  shall be used to repay  outstanding  Advances and
                  the Commitment shall be permanently reduced,  unless otherwise
                  agreed to by Borrower  and  Lender,  by the amount of Lender's
                  participation in such equity offering.

                           D. Borrower may  permanently  terminate or reduce the
                  Commitment  at any time upon two Business  Days' prior written
                  notice or by  telephone  (promptly  confirmed  in  writing) to
                  Lender in a minimum  amount of  $5,000,000;  provided that the
                  Commitment  may not be reduced to an amount less than the then
                  outstanding  principal  amount of all  Advances.  All  accrued
                  commitment  fees  shall be paid on the  effective  date of any
                  such reduction or termination.

                           E.  Borrower  may  voluntarily  at  any  time  prepay
                  Advances upon three Business Days' advance notice to Lender in
                  an  amount  not  less  than  $5,000,000.  Any  prepayments  of
                  Advances  shall  be  accompanied  by the  payment  of  accrued
                  interest on the amount  prepaid.  In case of  prepayment of an
                  Advance, or upon the failure to borrow an Advance after having
                  given notice thereof,  Borrower shall, upon demand, compensate
                  Lender  for  any  funding  losses  arising  from  any  funding
                  commitment  made by Lender  with  respect  to such  Advance to
                  Borrower and arising from Borrower's  prepayment or failure to
                  borrow such Advance.

                           F.  Obligations  of the  Borrower  to repay  Advances
                  shall be evidenced by a Note executed by the Borrower  payable
                  to  the  order  of  the  Lender  representing  the  Borrower's
                  obligation  to pay the Lender's  Commitment  or, if less,  the
                  aggregate  unpaid principal amount of all Advances made by the
                  Lender  to the  Borrower,  plus  interest  on  such  principal
                  amounts  and all other  fees,  charges  and other  amounts due
                  thereon.  The Note shall be dated the date hereof,  shall bear
                  interest  on  the  unpaid  principal  amount  thereof  at  the
                  applicable  interest  rate  specified  in this  agreement  and
                  otherwise shall be in the form attached hereto as Exhibit A.




II.      Availability:

                           A.  Advances may be requested as Base Rate  Advances,
                  WIBOR Advances and LIBOR Advances, as selected by Borrower, as
                  follows:






                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 3


                    1.  Base Rate Advances shall be available on any
                        Business Day upon notice given before 9:00 a.m. (Central
                        time) on the day of such Advance.

                                            2.  WIBOR  Advances  in  amounts  of
                           $25,000,000   or  less  shall  be  available  on  any
                           Business  Day upon  notice  given  before  9:00  a.m.
                           (Central time) on the day of such Advance.

                                            3. WIBOR Advances in amounts greater
                           than  $25,000,000  shall be available on any Business
                           Day upon one Business Days' prior notice given before
                           1:00 p.m. (Central time).

                                            4.  Unless  Lender  shall  otherwise
                           agree,  no WIBOR  Advance shall be for a Term greater
                           than 90 days.

                                            5. LIBOR Advances shall be available
                           on any  Business Day upon four  Business  Days' prior
                           notice  given  before  1:00 p.m.  (Central  time) and
                           shall have interest periods of one, two, three or six
                           months.

                                            6. Each notice of borrowing shall be
                           by  telephone   and  shall   specify  the   requested
                           borrowing  date,  the principal  amount and length of
                           interest period (if a LIBOR Rate Advance) or Term (if
                           a WIBOR Advance) for such Advance. Base Rate Advances
                           shall be in a minimum  principal amount of $5,000,000
                           and multiples of $1,000,000 in excess of such minimum
                           amount.   LIBOR   Advances  shall  be  in  a  minimum
                           principal  amount of  $10,000,000  and  multiples  of
                           $1,000,000  in excess  of such  minimum  amount.  The
                           exact duration of interest  periods relating to LIBOR
                           Advances   shall  be  subject  to  the   customs  and
                           practices  of the  funding  markets  for such type of
                           Advance.  No interest period for LIBOR Advances shall
                           expire  after the  Maturity  Date.  No WIBOR  Advance
                           shall  expire  later than 90 days after the  Maturity
                           Date, provided however, that if this agreement is not
                           amended and restated  prior to the  Maturity  Date to
                           extend the Maturity Date beyond the  expiration  date
                           of any outstanding Advances, all outstanding Advances
                           as  of  the  Maturity  Date,  together  with  accrued
                           interest and fees  thereon,  shall be due and payable
                           on the Maturity Date.

                           B. Upon four Business Days' prior notice given before
                  1:00 p.m.  (Central time), a LIBOR Advance may be continued on
                  the last day of its interest  period as a LIBOR Advance,  or a
                  Base Rate  Advance or WIBOR  Advance may be  converted  into a
                  LIBOR Advance.  Upon notice given on any Business Day prior to
                  9:00  a.m.  (Central  time)  in  the  event  such  Advance  is
                  $25,000,000 or less, or, upon one





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 4


                  Business  Days' prior notice  given before 1:00 p.m.  (Central
                  time) in the event such Advance is greater than $25,000,000, a
                  LIBOR  Advance may be  converted  into a WIBOR  Advance on the
                  last day of its  interest  period.  Upon  notice  given on any
                  Business Day prior to 9:00 a.m. (Central time) a LIBOR Advance
                  may be  converted  into a Base Rate Advance on the last day of
                  its  interest  period.  If  Borrower  fails  to give a  notice
                  described above prior to the end of any  expiration,  Borrower
                  shall be deemed to have requested that the maturing Advance be
                  converted into a Base Rate Advance.

                           C. If at any time  Lender,  in its  sole  discretion,
                  determines  that  the  LIBOR  Rate  or  WIBOR  Rate  does  not
                  accurately  reflect the funding cost to Lender of lending such
                  Advances,  Lender's obligation to make LIBOR Advances or WIBOR
                  Advances,  as the case may be, shall cease during such period.
                  If at any time Lender, in its sole discretion, determines that
                  adequate resources are not available to support the lending of
                  WIBOR  Advances,  Lender's  obligation to make WIBOR  Advances
                  shall cease during such period.

                  III.     Pricing:

                           A. Each Base Rate  Advance  shall bear  interest at a
                  floating  rate equal to the Base Rate plus 112.5 basis  points
                  per annum, payable in arrears on the last Business Day of each
                  quarter and on the Maturity Date.

                           B. Each WIBOR  Advance shall bear interest at a fixed
                  rate equal to the WIBOR Rae plus 112.5 basis points per annum,
                  payable  monthly in arrears on the first  Business Day of each
                  month and on the Maturity Date.

                           C. Each LIBOR  Advance shall bear interest at a fixed
                  rate per annum equal to the LIBOR Rate plus 112.5 basis points
                  per  annum,  payable on the last day of each  interest  period
                  and,  with respect to advances with  interest  periods  longer
                  than  three  months,  at the end of the  third  month  of such
                  advance.

                           D.  Borrower  shall pay a commitment  fee equal to 30
                  basis points per annum on the daily average unutilized portion
                  of the  Commitment  for the period  commencing  on the Closing
                  Date and ending on the  Maturity  Date,  payable  quarterly in
                  arrears and on the Maturity Date. All Commitment Fees shall be
                  computed on the basis of the actual  number of days elapsed in
                  a year of 360 days.

                           E. All amounts not paid when due hereunder shall bear
                  interest,  to the extent permitted by law, at a per annum rate
                  which is equal to the Base Rate plus 2 percent. Upon any Event
                  of Default under  Paragraph IX A, B or C, all Advances  shall,
                  at Lender's option, be





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 5


                  converted into Base Rate Advances.  Upon any Event of Default,
                  Borrower may not request  Advances to be made or continued as,
                  or converted  into,  LIBOR Advances or WIBOR Advances  without
                  Lender's consent.

                           F. All interest on LIBOR  Advances and WIBOR Advances
                  shall  be  calculated  on the  basis of a year of 360 days and
                  actual days elapsed which results in greater  interest than if
                  a 365/366  day-year were used.  Interest on Base Rate Advances
                  shall be calculated on the basis of a year of 365/366 days and
                  actual days elapsed.

IV.      Payments:

                           A. All  payments to Lender shall be made at 818 South
                  Kansas Avenue, Topeka, Kansas 66612, or such other location or
                  bank  account(s)  as Lender  may from time to time  specify in
                  same day funds not later than 12:00 noon (Central time).

                           B.  Borrower  shall  make  all  payments  under  this
                  agreement free and clear of any deduction for any future taxes
                  (other than any withholding  taxes),  and reimburse Lender for
                  any future taxes  assessed on or withheld  from such  payments
                  (except  franchise taxes and taxes assessed on the net income,
                  gross receipts or capital of Lender).

                           C. All amounts due  hereunder  shall be  evidenced by
                  entries in records maintained by Lender, which shall be deemed
                  accurate in all  respects,  absent  manifest  error;  provided
                  however,  the failure of Lender to maintain any such  records,
                  or any error  therein,  shall  not in any  manner  affect  the
                  obligation  of  Borrower  to  repay  any  Advances  and  other
                  obligations in accordance with the terms hereof.

                           D. Borrower  shall  reimburse or  compensate  Lender,
                  upon demand, for all material costs incurred,  losses suffered
                  or payments  made by Lender  which are  applied or  reasonably
                  allocated by Lender to the  transactions  contemplated  herein
                  (all as determined by Lender in its reasonable  discretion) by
                  reason of:

                                            1.  Any  and  all  future   reserve,
                           deposit,  capital  adequacy  or similar  requirements
                           against  (or  against any class of or change in or in
                           the  amount  of)   assets  or   liabilities   of,  or
                           extensions of credit by, Lender; and

                                            2.  Compliance  by  Lender  with any
                           direction  or   requirements   from  any   regulatory
                           authority, whether or not having the force of law.





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 6



V.       Conditions for use of Facility:

         A.       Initial Extension of Credit.  As a condition precedent to
                  the first use of this facility, Lender must have received the
                  following, in form and substance satisfactory to Lender:

                           1.       This agreement and Note, duly executed and
                           delivered by Borrower.

                                            2. Parental Guaranty,  duly executed
                           and delivered by Parent attached hereto as Exhibit B.

                                            3.   Affiliate   Guaranties,    duly
                           executed and delivered by Westar  Security,  Inc. and
                           WestSec,  Inc.  attached  hereto  as  Exhibit  C  and
                           Exhibit D, respectively.

                                            4. Pledge  Agreement,  duly executed
                           and delivered by Parent and  Borrower,  together with
                           certificates    representing   all   of   Borrower's,
                           WestSec's,  and Westar Security's  capital stock with
                           executed  stock powers  ("Pledged  Shares")  attached
                           hereto as Exhibit E.

                                            5.  Articles  of   incorporation  of
                           Borrower  certified  by the  secretary  of  state  of
                           Borrower's incorporation.

                                            6. Borrower's by-laws,  certified by
                           the secretary or an assistant secretary of Borrower.

                                            7.   Corporate    resolutions   with
                           certificate of incumbency evidencing the authority of
                           the officer(s)  executing this agreement on behalf of
                           Borrower.

                                            8.   Corporate    resolutions   with
                           certificate of incumbency evidencing the authority of
                           the  officer(s)  executing the  Guaranties and Pledge
                           Agreement.

                                            9.  Legal   opinion  of   Borrower's
                           counsel as to such  matters  reasonably  requested by
                           Lender.

                                            10.  A  certificate  of a  financial
                           officer of Borrower stating that the  representations
                           and  warranties  set forth in  Paragraph VI below are
                           correct in all  material  respects  on and as of such
                           date  as  though  made on such  date,  except  to the
                           extent such  representations and warranties expressly
                           relate to an earlier date.

                           11.  Payment of Lender's legal costs and expenses.





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 7



                                            12.  All   amounts   due  under  the
                           Promissory Notes,  dated January 1, 1998 and March 2,
                           1998,  between  Borrower  and Lender shall be paid in
                           full with the proceeds of the first Advance hereunder
                           and the Promissory Notes cancelled.

                                            13.  Such  other  documents  as  the
                           Lender  may  reasonably  request  in order to  effect
                           fully the purposes of this agreement.

                           B. Each Extension of Credit. As a condition precedent
                  to all Advances, the following conditions must be satisfied:

                                            1. Each  representation and warranty
                           set  forth in  paragraph  VI below  shall be true and
                           correct  as if made on the date of such use (and each
                           request  for an  Advance  shall be  deemed a  further
                           representation that such are true and correct).
                                            2. No Event of  Default  or event or
                           condition  which,  with  the  passage  of time or the
                           giving of notice,  or both,  shall become an Event of
                           Default, shall have occurred under this agreement.

 VI.      Representations and Warranties:  Borrower represents and warrants to
          Lender that:

                           A.  Borrower,  Parent  and each of  their  respective
                  Subsidiaries:  (a) is a corporation  duly  organized,  validly
                  existing  and  in  good   standing   under  the  laws  of  the
                  jurisdiction  of its  incorporation;  (b)  has the  power  and
                  authority  and  all  governmental  licenses,   authorizations,
                  consents  and  approvals  to  own  its  assets,  carry  on its
                  business as currently conducted, and to execute,  deliver, and
                  perform its obligations  under this agreement if it is a party
                  hereto; and (c) is duly qualified as a foreign corporation and
                  is  licensed  and in  good  standing  under  the  laws of each
                  jurisdiction  where  its  ownership,  lease  or  operation  of
                  property  or  the  conduct  of  its  business   requires  such
                  qualification or license;  except, in each case referred to in
                  clauses  (b) and (c) above,  to the extent that the failure to
                  do so would not  reasonably  be  expected  to cause a Material
                  Adverse Change.

                           B.  The  execution,   delivery  and   performance  by
                  Borrower of this  agreement  does not and will not (a) violate
                  any  provision of law, the  certificate  of  incorporation  or
                  bylaws of  Borrower  or any order,  judgment  or decree of any
                  court or other agency of government  binding on Borrower where
                  such  violation  would  reasonably  be  expected  to  cause  a
                  Material  Adverse  Change,  or (b) conflict with,  result in a
                  breach of or constitute (with due





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 8


                  notice or lapse of time or both) a default  under any material
                  agreement  or  instrument  to which  Borrower is a party or by
                  which any of its  properties  or assets is bound,  where  such
                  conflict,  breach or default  would  reasonably be expected to
                  cause a Material Adverse Change.

                           C. No approval, consent, exemption, authorization, or
                  other   action  by,  or  notice  to,  or  filing   with,   any
                  governmental  authority is necessary or required in connection
                  with the execution, delivery or performance by, or enforcement
                  against, Borrower of this agreement.

                           D. This agreement  constitutes  the legal,  valid and
                  binding obligations of Borrower,  enforceable against Borrower
                  in accordance with its terms,  except as enforceability may be
                  limited by applicable bankruptcy,  insolvency, or similar laws
                  affecting the enforcement of creditors' rights generally or by
                  equitable principles relating to enforceability.

                           E.  Borrower is not in violation of any material term
                  of any lease, contract, agreement or instrument to which it is
                  a party where such violation  would  reasonably be expected to
                  cause a Material Adverse Change.

                           F. No Event of Default or event or  condition  which,
                  with the  passage of time or the  giving of  notice,  or both,
                  shall  become  an  Event  of  Default,  has  occurred  and  is
                  continuing.

                           G.  Borrower's  audited  financial  statements  dated
                  December 31,  1997,  and the related  statements  of income or
                  operations, shareholders' equity and cash flows for the fiscal
                  year ended on that date were prepared in accordance  with GAAP
                  consistently  applied  throughout the periods covered thereby,
                  except as otherwise expressly noted therein and fairly present
                  the financial condition of Borrower and its subsidiaries as of
                  the dates  thereof and results of  operations  for the periods
                  covered  thereby.  Since December 31, 1997,  there has been no
                  Material Adverse Change.

                           H.  There is no  litigation,  proceeding  or  dispute
                  pending or, to the best of  Borrower's  knowledge,  threatened
                  against  Borrower  or  any  of its  Subsidiaries  which  would
                  reasonably be expected to result in a Material  Adverse Change
                  or  purport  to  affect  Borrower's   obligations  under  this
                  agreement, or any of the transactions contemplated hereby.

                           I.  Each Plan is in compliance in all material 
                  respects with the applicable provisions of ERISA, the Code and
                  other federal or state law.  There are no pending, or to the
                  best knowledge of





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 9


                  Borrower, threatened claims, actions or lawsuits, or action by
                  any governmental authority, with respect to any Plan which has
                  caused or would  reasonably  be  expected  to cause a Material
                  Adverse Change.  The aggregate  unfunded pension liability for
                  each such Plan does not exceed $100,000.

                           J.  Borrower  has good and  sufficient  title  to, or
                  valid leasehold  interest in, all of its properties and assets
                  except where the failure  would not  reasonably be expected to
                  cause a Material Adverse Change.

                           K.  Borrower  and its  Subsidiaries  have  filed  all
                  Federal and other material tax returns and reports required to
                  be filed,  and have paid all Federal and other material taxes,
                  assessments,  fees and other  governmental  charges  levied or
                  imposed  upon  them or  their  properties,  income  or  assets
                  otherwise  due and  payable,  except  those  which  are  being
                  contested  in good faith by  appropriate  proceedings  and for
                  which adequate  reserves have been provided in accordance with
                  GAAP.

                           L.  Borrower  conducts  in  the  ordinary  course  of
                  business  a review  of the  effect of  existing  environmental
                  laws,   regulations,   and   guidelines   and  claims  on  its
                  properties,  and as a result  thereof  Borrower has reasonably
                  concluded that such  environmental  laws and claims would not,
                  individually  or in the  aggregate,  reasonably be expected to
                  cause a Material Adverse Change.


                           M.  Borrower  is not  subject to the  Public  Utility
                  Holding Company Act of 1935, as amended.

                           N.  Borrower  is not  an  "investment  company"  or a
                  company  "controlled" by an "investment  company,"  within the
                  meaning of the Investment Company Act of 1940, as amended.

                           O. None of the  statements  contained in any exhibit,
                  report,  statement  or  certificate  furnished  by Borrower to
                  Lender in connection  with this Agreement  contains any untrue
                  statement  of a  material  fact or  omits  any  material  fact
                  required  to be  stated  therein  or  necessary  to  make  the
                  statements made therein,  in light of the circumstances  under
                  which they are made,  not  misleading as of the time when made
                  or delivered in each case where such material  misstatement or
                  omission  would  reasonably be likely to adversely  affect the
                  rights or interests of Lender.

         VII.     Affirmative Covenants:  Until the Commitment has terminated
         and all indebtedness of Borrower hereunder to Lender has been paid in
         full, Borrower, unless Lender shall consent in writing:





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 10



         A.       Shall provide to Lender:

                                            1.   annual   financial   statements
                           prepared in  accordance  with GAAP,  together with an
                           opinion  of its  independent  accountants  within 120
                           days of each fiscal year-end of Borrower  unqualified
                           as to scope of audit or going concern;

                                            2.    quarterly     company-prepared
                           financial statements prepared in accordance with GAAP
                           within 90 days of the end of each of Borrower's first
                           three fiscal quarters;

                                            3.  together  with  delivery  of the
                           financial statements referred to above, a certificate
                           from  the  Chief   Financial   Officer  of   Borrower
                           certifying  no  Event of  Default  has  occurred  and
                           demonstrating compliance with the covenants contained
                           in paragraph F of Section VIII;

                                            4.  promptly  upon  their   becoming
                           available,   copies  of  all  financial   statements,
                           reports,  notices and proxy  statements  sent or made
                           available  generally  by  Borrower  to  its  security
                           holders,  including all regular and periodic  reports
                           and all prospectuses that have been filed by Borrower
                           with any  securities  exchange or with the Securities
                           and Exchange Commission, except prospectuses relating
                           to benefit plans filed under Form S-8;

                                            5. written  notice of the occurrence
                           of any Event of Default or any event which,  with the
                           lapse of time or  notice  or both,  would  become  an
                           Event of Default; and

                                            6. such other information  regarding
                           the  operations,   business   affairs  and  financial
                           condition of Borrower or any Subsidiary or compliance
                           with the terms of the  Agreement  as Lender  may from
                           time to time reasonably request.

                           B.  Will,  and will  cause  Parent  and each of their
                  respective  Subsidiaries to, at all times preserve and keep in
                  full force and effect their corporate existence and all rights
                  and franchises material to their business.

                           C.  Will maintain or cause to be maintained  in good
                  repair,  working order  and  condition  all  material
                  properties  used  in the business of Borrower, Parent and'
                  their respective Subsidiaries and will  make or cause  to be
                  made all  appropriate  repairs, renewals and replacements
                  thereof.  Borrower will maintain or cause to be maintained,
                  with financially





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 11


                  sound and reputable  insurers,  public  liability and property
                  damage  insurance  with respect to its business and properties
                  and the business and properties of Parent and their respective
                  Subsidiaries  against loss or damage of the kinds  customarily
                  carried  or  maintained   by   corporations   of   established
                  reputation  engaged  in  similar  businesses  and  in  amounts
                  acceptable  to Lender  and will  deliver  evidence  thereof to
                  Lender.

                                       D.
                  Will  and  will  cause  Parent  and  each  of their respective
                  Subsidiaries  to  (a)  comply  with  the  requirements  of all
                  applicable  laws,   rules,   regulations  and  orders  of  any
                  governmental  authority  as now in  effect  and  which  may be
                  imposed in the future in all  jurisdictions in which Borrower,
                  Parent or any such  Subsidiary  is now doing  business  or may
                  hereafter  be doing  business,  other than those laws,  rules,
                  regulations and orders the noncompliance  with which would not
                  reasonably be expected to have, either  individually or in the
                  aggregate, a Material Adverse Change, and (b) maintain, as the
                  case may be, all  licenses  and permits now held or  hereafter
                  acquired,  the loss,  suspension,  or revocation of which,  or
                  failure to renew, could have a Material Adverse Change.

                                       E.
                                       1.
               Shall       and shall cause  Parent and each of their  respective
                           Subsidiaries  to,  from  time to time,  execute  such
                           guaranties, financing statements, documents, security
                           agreements  and  reports  as  Lender  at any time may
                           reasonably request to evidence,  perfect or otherwise
                           implement the  guaranties  and security for repayment
                           of the obligations hereunder provided for in the Loan
                           Documents.  Without  limiting the  generality  of the
                           foregoing,  Lender  may  at  any  time  request  that
                           Borrower  cause  Parent and each of their  respective
                           Subsidiaries   to   secure   Borrower's   obligations
                           hereunder and the obligations under the Guaranties in
                           a manner  satisfactory to Lender,  and Borrower shall
                           cause   Parent   and   each   of   their   respective
                           Subsidiaries to comply therewith.


                                                         2.
                  At       Lender's  request,  shall  cause  Parent  and each of
                           their  respective  Subsidiaries  promptly to guaranty
                           the  Borrower's  and Parent's  obligations  under the
                           Loan  Documents  and to grant to  Lender,  a security
                           interest in the real,  personal and mixed property of
                           any such  Person  to  secure  such  obligations.  The
                           documentation  for such guaranty or security shall be
                           in such form and substance as Lender shall reasonably
                           request.






                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 12


         VIII. Negative Covenants: Borrower covenants and agrees that so long as
         any of the  Commitment  remains in effect and until  payment in full of
         all obligations under the Loan Documents, unless Lender shall otherwise
         give its prior written  consent,  Borrower  shall comply with and shall
         cause Parent and each of their  respective  Subsidiaries to comply with
         all covenants in this Section VIII applicable to such Person.

                                       A.
                    Borrower will not, nor will Borrower permit Parent or any of
                  their  respective  Subsidiaries  directly  or  indirectly  to,
                  create, incur, assume, guaranty, or otherwise become or remain
                  directly or indirectly liable with respect to any Indebtedness
                  except  the  obligations   under  the  Loan   Documents,   any
                  Indebtedness  outstanding  on the  date  hereof,  intercompany
                  Indebtedness  among  Borrower  and  its  affiliates  which  is
                  unsecured and  subordinate to the  obligations to Lender,  and
                  Indebtedness not exceeding $25,000,000.

                                       B.
                    Borrower will not, nor will Borrower permit Parent or any of
                  their  respective   Subsidiaries  directly  or  indirectly  to
                  create,  incur,  assume or permit to exist any Lien on or with
                  respect to any  property or asset  (including  any document or
                  instrument  with respect to goods or accounts  receivable)  of
                  Borrower,  Parent  or any of  their  respective  Subsidiaries,
                  whether  now owned or  hereafter  acquired,  or any  income or
                  profits therefrom, except Permitted Encumbrances.

                                       C.
                    Borrower will not, nor will Borrower permit Parent or any of
                  their  respective  Subsidiaries  to,  enter into or assume any
                  agreement  (other than the Loan  Documents,  the  Subordinated
                  Discount  Note  Indenture  and  the  documents  governing  the
                  Convertible  Notes)  prohibiting the creation or assumption of
                  any Lien upon its properties or assets,
                  whether now owned or hereafter acquired.

                                       D.
                Except as provided  herein and under the  Subordinated  Discount
                  Note  Indenture  and the documents  governing the  Convertible
                  Notes,  Borrower will not, nor will Borrower  permit Parent or
                  any of their respective Subsidiaries,  directly or indirectly,
                  to  create  or  otherwise  cause or  suffer to exist or become
                  effective any  consensual  encumbrance  or  restriction of any
                  kind  on the  ability  of  Borrower,  Parent  or any of  their
                  respective  Subsidiaries  to:  (1) pay  dividends  or make any
                  other distribution on such Person's capital stock; (2) subject
                  to  subordination  provisions,  pay any  indebtedness  owed to
                  Parent, Borrower or any of their respective Subsidiaries;  (3)
                  make loans or advances to Parent,  Borrower or any  Subsidiary
                  of Borrower;  or (4) transfer any of its property or assets to
                  Parent, Borrower or any of Borrower's Subsidiaries.





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 13



                                       E.
                                       1.
                    Borrower will not, nor will Borrower permit Parent or any of
                           their   respective   Subsidiaries  to  sell,   lease,
                           transfer or otherwise dispose of any of its property,
                           business or assets,  or grant any Person an option to
                           acquire any such property,  business or assets except
                           for (a) bona fide sales of inventory to customers for
                           fair value in the  ordinary  course of  business  and
                           dispositions of obsolete equipment not used or useful
                           in the business,  (b) mergers and transfers of assets
                           among Borrower and its Subsidiaries  provided no such
                           transfer  or merger  may result in a Default or Event
                           of Default; (c) sales of subscriber accounts which do
                           not  result in a  Material  Adverse  Change;  and (d)
                           other  Asset  Dispositions  if all  of the  following
                           conditions  are met:  (i) the market  value of assets
                           sold  or   otherwise   disposed   of  in  any  single
                           transaction  or series of related  transactions  does
                           not exceed  $5,000,000 and the aggregate market value
                           of assets sold or otherwise disposed of in any Fiscal
                           Year   does   not   exceed   $10,000,000;   (ii)  the
                           consideration  received is at least equal to the fair
                           market value of such  assets;  (iii) the Net Proceeds
                           of such  Asset  Disposition  are  applied  to  reduce
                           outstanding Advances;  (v) after giving effect to the
                           sale or  other  disposition  of the  assets  included
                           within the Asset  Disposition  and the  repayment  of
                           Indebtedness with the proceeds  thereof,  Borrower is
                           in compliance on a pro forma basis with the covenants
                           set forth in  Section  VIII  recomputed  for the most
                           recently   ended  month  for  which   information  is
                           available and is in  compliance  with all other terms
                           and conditions contained in this agreement;  and (vi)
                           no Default or Event of Default shall result from such
                           sale or other disposition.


                                                         2.
                Except     as permitted  elsewhere in this  agreement,  Borrower
                           will not, nor will  Borrower  permit Parent or any of
                           their respective  Subsidiaries directly or indirectly
                           to sell,  assign,  pledge or  otherwise  encumber  or
                           dispose  of any  shares  of  capital  stock  or other
                           equity  securities  in Borrower,  WestSec,  or any of
                           their or Parent's  Subsidiaries  including  warrants,
                           rights or options to acquire  shares or other  equity
                           securities of any such Person.


                                                         3.
                           Borrower  and  WestSec  shall at all  times be direct
                           wholly-owned Subsidiaries of Parent.

                  F.Borrower will not permit its Leverage Ratio to exceed 6.0 to
                  1.

                  G. Borrower will not use any portion of the loan proceeds,  to
                  purchase or carry margin stock, as defined in Regulation G, T,
                  U or X of the Federal Reserve Board.

IX.    Events of Default:  If any of the following events ("Events of Default")
       shall occur:

       A.       Borrower fails to pay any principal of any Advance when due;
                or

       B.       Borrower fails to pay any interest on any Advance within
                  three days after becoming due; or

       C. Borrower fails to pay any other amount (other than
          an  amount  referred  to in A or B  above)  when  due and such
                  default  shall  continue  unremedied  for a period of ten days
                  following notice from Lender; or

                           D. Any representation or warranty made by Borrower or
                  Parent to Lender in any  documents or  agreements  relating to
                  this  facility  proves to be in any material  respect false or
                  misleading; or

                           E.  Borrower  fails  to  comply  with  (i)  Paragraph
                  VII.A.5, VII.E or VIII, or (ii) any other condition,  covenant
                  or  obligation  contained  herein  or  in  any  agreements  or
                  instruments  related  hereto and such default  shall  continue
                  unremedied  for a period of 30 days after notice  thereof from
                  Lender to Borrower; or

                           F. Any  default  occurs  under  any  other  agreement
                  involving  the  extension  of credit in excess of  $500,000 in
                  recourse debt to which  Borrower,  Parent or their  respective
                  Subsidiaries  may be  obligated  as borrower  (if such default
                  gives the holder of the obligation the right to accelerate the
                  indebtedness); or

                           G. If (i) any Plan  subject  to Title IV of ERISA and
                  maintained  for the  employees of Borrower,  Parent,  or their
                  respective   Subsidiaries  shall  be  terminated  pursuant  to
                  Subtitle  C of  Title IV of  ERISA,  (ii) a  trustee  shall be
                  appointed by the  appropriate  United States District Court to
                  administer  any such  Plan,  (iii)  the PBGC  shall  institute
                  proceedings  to terminate any such Plan, or (iv) any such Plan
                  fails to satisfy the minimum  funding  standard  for such Plan
                  for a Plan year as established in Section





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 14


                  412 of the Internal  Revenue  Code,  as amended and such event
                  under any of G(i)-(iv) would  reasonably be expected to result
                  in a Material Adverse Change; or

                           H. Any  agreement or instrument  required  hereunder,
                  which  materially   affects  Lender's  rights  or  Borrower's,
                  Parent's or their  respective  Subsidiaries'  obligations,  is
                  terminated, breached or ceases to be effective; or

                           I. The loss,  suspension or revocation of, or failure
                  to renew, any license or permit now held or hereafter acquired
                  by Borrower,  Parent or any of their respective  Subsidiaries,
                  if such loss, suspension, revocation or failure to renew could
                  have a Material Adverse Change; or

                                       J.
                Lender does not have or  ceases  to have a valid  and  perfected
                  first priority  security  interest in the Pledged  Shares,  in
                  each case,  for any reason other than the failure of Lender to
                  take any action within its control; or

           K.       Lender fails to own, directly or indirectly, 51% or more of
                 the outstanding capital stock of Borrower and Parent; or

           L.       Pledge Agreement and/or Guaranties are terminated, breached
                 or ceases to be effective; or

                           M.  Any  bankruptcy,   reorganization,   arrangement,
                  insolvency, dissolution or similar proceeding is instituted by
                  or  against  Borrower,  Parent  or  any  of  their  respective
                  Subsidiaries  under  the laws of any  jurisdiction  and,  with
                  respect   to  any   involuntary   bankruptcy   or   insolvency
                  proceeding,  such proceeding remains  undismissed for a period
                  of 60 days;

                                    THEN,  Lender  may,  by  written  notice  to
                  Borrower, (i) declare Lender's Commitment to extend additional
                  credit  hereunder to be  terminated,  whereupon the Commitment
                  shall  be  terminated,   (ii)  declare  all  sums  outstanding
                  hereunder  or under  any  instrument  executed  in  connection
                  herewith to be immediately  due and payable  together with all
                  interest thereon,  all without notice of default,  presentment
                  or demand  for  payment,  protest or notice of  nonpayment  or
                  dishonor,   or  other  notices  or  demands  of  any  kind  or
                  character, all of which are hereby expressly waived; provided,
                  however,  that upon the  occurrence of any event  specified in
                  paragraph  VIII.M  above,  any  Commitment by Lender to extend
                  additional credit hereunder shall automatically terminate, all
                  sums outstanding hereunder or under any instrument executed in
                  connection  herewith shall become  immediately due and payable
                  together with all





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 15


                  interest thereon,  all without notice of default,  presentment
                  or demand  for  payment,  protest or notice of  nonpayment  or
                  dishonor,   or  other  notices  or  demands  of  any  kind  or
                  character, all of which are hereby expressly waived.

         X.  Indemnity:  In  addition  to  the  payment  of  expenses  and  fees
         hereunder,  Borrower  agrees to indemnify,  pay and hold Lender and any
         holder of any of the Notes,  and the  officers,  directors,  employees,
         agents,   affiliates   and   attorneys   of  Lender  and  such  holders
         (collectively  called the "Indemnitees")  harmless from and against any
         and all liabilities,  obligations, losses, damages, penalties, actions,
         judgments,  suits, claims,  liabilities for taxes,  broker's or finders
         fees,  costs,   expenses  and  disbursements  of  any  kind  or  nature
         whatsoever  (including the fees and  disbursements  of counsel for such
         Indemnitees in connection  with any  investigative,  administrative  or
         judicial  proceeding  commenced  or  threatened,  whether  or not  such
         Indemnitee shall be designated a party thereto) that may be imposed on,
         incurred  by,  or  asserted  against  that  Indemnitee,  in any  manner
         relating to or arising out of (a) the negotiation, execution, delivery,
         performance,   administration,  or  enforcement  of  any  of  the  Loan
         Documents,  (b)  any  of the  transactions  contemplated  by  the  Loan
         Documents,  (c) any breach by Borrower or Parent of any representation,
         warranty,  covenant,  or other  agreement  contained in any of the Loan
         Documents,  (d) Lender's agreement to make the Advances hereunder,  (g)
         the use or intended use of the proceeds of any of the Advances, (h) any
         and all taxes, levies,  deductions and charges imposed on Lender or any
         of Lender's  correspondents  in respect of any Advance  (the  foregoing
         liabilities  herein  collectively   referred  to  as  the  "Indemnified
         Liabilities");  provided that  Borrower  shall have no obligation to an
         Indemnitee  hereunder with respect to Indemnified  Liabilities  arising
         from the gross  negligence or willful  misconduct of that Indemnitee as
         determined by a court of competent jurisdiction. To the extent that the
         undertaking  to  indemnify,  pay and  hold  harmless  set  forth in the
         preceding sentence may be unenforceable  because it is violative of any
         law or public  policy,  Borrower shall  contribute the maximum  portion
         that it is permitted  to pay and satisfy  under  applicable  law to the
         payment and satisfaction of all Indemnified Liabilities incurred by the
         Indemnitees or any of them.

XI.      Miscellaneous.

                           A.  Borrower  shall  pay  Lender,   on  demand,   all
                  reasonable  out-of-pocket  expenses and legal fees  (including
                  the allocated costs for in-house legal  services)  incurred by
                  Lender in connection  with the  enforcement  of this agreement
                  and any instruments or agreements  executed in connection with
                  this agreement.






                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 16


                           B. This  letter  agreement  shall be  governed by and
                  construed in accordance  with the laws of the state of Kansas,
                  to the  jurisdiction  of whose courts,  both state and federal
                  all signatories hereto submit.

                           C. This letter  supersedes  all prior  agreements and
                  oral  negotiations  with respect to the subject matter of this
                  letter.  This  agreement is not assignable by Borrower and any
                  purported  assignment is void.  Lender may, at any time, grant
                  participations  in all or part of its rights  and  obligations
                  hereunder  and/or  assign  all or any part of its  rights  and
                  obligations hereunder.

                           D. No delay or  omission  by Lender to  exercise  any
                  right under this letter or under any document  related  hereto
                  shall impair such right, nor shall it be construed as a waiver
                  thereof.  No waiver of any breach or default shall be deemed a
                  waiver of any  subsequent  breach or default.  Any  amendment,
                  waiver,  consent  or  approval  under this  letter  must be in
                  writing to be effective.

                           E.   Paragraph   headings  in  this  letter  are  for
                  reference only and shall not affect the  interpretation of any
                  provision of this letter.

                           F. Except as  otherwise  expressly  provided  herein,
                  notices and other communications  provided for herein shall be
                  in writing and shall be delivered by hand or overnight courier
                  service,   mailed  or  sent  by  telex,   telecopy   or  other
                  telegraphic  communications equipment of the sending party, as
                  follows:  (a) if to Borrower,  to it at 4221 W. John Carpenter
                  Fwy, Irving,  TX 75063,  Attention of David Peters,  Facsimile
                  No. (972) 916-6156;  and (b) if to Lender,  to it at 818 South
                  Kansas  Avenue,  Topeka,  Kansas  66612,  Attention of E. Lynn
                  Cook, Facsimile No. (785) 575-1930.

                           G. Waiver of Jury Trial.  TO THE EXTENT  PERMITTED BY
                  APPLICABLE LAW, LENDER AND BORROWER HEREBY  IRREVOCABLY  WAIVE
                  THEIR  RESPECTIVE  RIGHTS TO A JURY TRIAL WITH  RESPECT TO ANY
                  ACTION,  CLAIM OR OTHER PROCEEDING  ARISING OUT OF ANY DISPUTE
                  IN CONNECTION WITH THIS AGREEMENT,  THE NOTE OR ANY OTHER LOAN
                  DOCUMENT,  ANY RIGHTS OR OBLIGATIONS  HEREUNDER OR THEREUNDER,
                  OR THE PERFORMANCE OF SUCH RIGHTS AND OBLIGATIONS.

                           H.   Notwithstanding  any  other  provision  of  this
                  agreement, in no event shall the interest payable on Advances,
                  whether before or after maturity,  exceed the maximum interest
                  which, under applicable law, may be charged.





                  PROTECTION ONE ALARM MONITORING, INC.
                  April 1, 1998
                  Page 17


                  Please  indicate your  acceptance  of the foregoing  terms and
conditions by signing and returning a copy of this letter.


                                                              Sincerely yours,



                                                            WESTAR CAPITAL, INC.



                                                 By:  \s\ Rita A. Sharpe
                                                 Name: Rita A. Sharpe_________
                                                 Title:  President_____




Agreed and Accepted:


PROTECTION ONE ALARM MONITORING, INC.


By: \s\ John W. Hesse
Name: _John W. Hesse
Title: Executive Vice President &
       Chief Financial Officer













                                  ATTACHMENT 1

                                   DEFINITIONS




                       Advance: a Base Rate Advance, a WIBOR Advance or a LIBOR
                       Advance (collectively, the "Advances").

     Asset
     Disposition:  the disposition whether by sale, lease, transfer, loss,
                   damage, destruction, condemnation or otherwise of any of the
                   following:  (a) any of the stock of any of Borrower's or
                   Parent's Subsidiaries; or (b) any or all of the assets of
                   Borrower, Parent or any of their respective Subsidiaries
                   other than sales of inventory in the ordinary course of
                   business.

                           Base Rate:  the  higher of: (a) the rate of  interest
                           publicly   announced  from  time  to  time  by  Chase
                           Manhattan Bank in New York, as its "Prime Rate,", (b)
                           one percent per annum above the secondary market rate
                           for three-month certificates of deposit (adjusted for
                           statutory  reserve  requirements),  and (c)  one-half
                           percent per annum above the Federal  Funds Rate.  Any
                           change in the Prime Rate announced by Chase Manhattan
                           Bank shall take  effect at the opening of business on
                           the day specified in the public  announcement of such
                           change.

Base Rate
Advance:                  an Advance bearing an interest rate based on the Base
                          Rate.

                           Business  Day:  (a) any day  other  than a  Saturday,
                           Sunday or other day on which  commercial banks in New
                           York City and the state of Kansas are  authorized  or
                           required by law to close and (b) in the case of LIBOR
                           Advances  and  WIBOR  Advances,  such a day on  which
                           dealings  are  also  carried  on  in  the  applicable
                           market.

                           Capital




                                                              - 18 -














                           Expenditures:  without  duplication,  for any period,
                           the aggregate of all  expenditures  on a consolidated
                           basis  including  deposits  (whether  paid in cash or
                           property or accrued as liabilities  and including the
                           aggregate  amount of all  principal  payments due for
                           the  entire  term of all  Capital  Leases  which  are
                           required to be capitalized on the balance sheet) made
                           by Borrower, Parent and their respective Subsidiaries
                           that,  in  conformity  with GAAP,  are required to be
                           included in the property,  plant,  or  equipment,  or
                           similar fixed asset account; provided, however, there
                           shall be  excluded  from the  calculation  of Capital
                           Expenditures   only   that   portion   of  all   such
                           expenditures   which   Borrower,   Parent  and  their
                           respective  Subsidiaries are permitted to reinvest or
                           use for  replacement or restoration of assets through
                           the use of insurance proceeds, awards of compensation
                           arising   from   condemnation   or   eminent   domain
                           proceedings   or   from   Net   Proceeds   of   Asset
                           Dispositions.

  Capital Lease:   any lease of any property (whether real, personal or mixed)
                   that, in conformity with GAAP, should be accounted for as a
                   capital lease.

  Closing Date:    the date this letter is executed by Borrower.

  Code:            the Internal Revenue Code of 1986, as the same
                   may be amended from time to time.

  Commitment:      $600,000,000.

  Consolidated
                           EBITDA:   for  any  period,   the   following,   each
                           calculated for such period: (a) Net Income;  plus (b)
                           any  provision  for (or less any benefit from) income
                           or franchise taxes included in the  determination  of
                           Net Income; plus (c) interest expense deducted in the
                           determination  of Net Income;  plus (d)  amortization
                           and depreciation deducted in the determination of Net
                           Income;  plus (e) losses  from (or less  gains  from)
                           Asset  Dispositions  or  other   non-recurring  items
                           included   in  the   determination   of  Net  Income,
                           including  gains  arising  from any  reduction in the
                           reserve for Transition  Costs maintained by Borrower,
                           Parent and their  respective  Subsidiaries;  less (f)
                           after tax extraordinary gains (or




                                                              - 19 -












                           plus after tax extraordinary losses) (in each case as
                           defined under GAAP).

                  Convertible
 Notes:           6 3/4% Convertible Senior Subordinated Notes due 2003
                  of Borrower.
                  Currency
 Agreement:        means any foreign exchange contract, currency swap
                   agreement or other similar agreement or arrangement designed
                   to protect Borrower, Parent or any of their respective
                   Subsidiaries against fluctuations in currency values to or
                   under which they are a party or a beneficiary on the closing
                   date or becomes a party or a beneficiary thereafter.

                           Deferred
                           Account
                           Acquisition
                           Price:  means, in connection with (i) the purchase of
                           Subscriber  Accounts,  or (ii) the acquisition of all
                           of the  outstanding  Capital  Stock of a Person where
                           the  principal  purpose  of  such  acquisition  is to
                           acquire  Subscriber  Accounts,  that  portion  of the
                           purchase price of such Subscriber Accounts or Capital
                           Stock that has been deferred to provide an offset for
                           future purchase price adjustments.

          ERISA:           the Employee Retirement Income Security Act of 1974,
                           as amended.

Federal
Reserve Board:   the Board of Governors of the Federal Reserve System, or any
                           successor thereto.

                           Indebtedness:  with respect to any Person at any date
                           of  determination  (without  duplication),   (i)  all
                           indebtedness of such Person for borrowed money,  (ii)
                           all  obligations  of such Person  evidenced by bonds,
                           debentures,   notes  or  other  similar   instruments
                           (except,  with  respect to Borrower,  the  promissory
                           notes  issued by  Borrower  in favor of Ion  Leasing,
                           Inc. (which  obligations have been defeased by a cash
                           deposit in a segregated  trust  account)),  (iii) all
                           obligations of such Person with respect of letters of
                           credit  or  other  similar   instruments   (including
                           reimbursement obligations




                                                              - 20 -














                           with respect  thereto),  (iv) all obligations of such
                           Person to pay the deferred and unpaid  purchase price
                           of property or services,  which purchase price is due
                           more than six months  after the date of placing  such
                           property  in  service  or taking  delivery  and title
                           thereto or the completion of such service, except (A)
                           Trade  Payables,  (B)  all  obligations  to  pay  any
                           Deferred Account Acquisition Price, provided that the
                           maximum  amount   excluded  from  the  definition  of
                           "Indebtedness" under this clause (B) shall not exceed
                           $5,000,000   in  the   aggregate   at  any   date  of
                           determination   and  (C)   compensation   payable  to
                           employees of such Person (or any subsidiary  thereof)
                           under  employee  benefit plans of such Person,  which
                           compensation  is deferred in the  ordinary  course of
                           business of such Person (or such  subsidiary)  and in
                           accordance  with such plans,  (v) all  Capital  Lease
                           Obligations of such Person,  (vi) all Indebtedness of
                           other Persons  secured by a Lien on any asset of such
                           Person,  whether or not such  Indebtedness is assumed
                           by such  Person;  provided  that the  amount  of such
                           Indebtedness  shall  be the  lesser  of (A) the  fair
                           market   value  of  such   asset  at  such   date  of
                           determination    and   (B)   the   amount   of   such
                           Indebtedness, (vii) all Indebtedness of other Persons
                           guaranteed   by  such   Person  to  the  extent  such
                           Indebtedness is guaranteed by such Person, (viii) all
                           outstanding  Redeemable  Stock  issued by such Person
                           and (ix) to the extent not otherwise included in this
                           definition, obligations under Currency Agreements and
                           Interest Rate Agreements.  The amount of Indebtedness
                           of any  Person at any date  shall be the  outstanding
                           balance at such date of all unconditional obligations
                           as described  above and,  with respect to  contingent
                           obligations  (other  than those  described  in clause
                           (vii)),  the maximum liability upon the occurrence of
                           the  contingency   giving  rise  to  the  obligations
                           (including  with respect to any premium  which may be
                           payable  on  the  redemption  of  Redeemable  Stock),
                           provided (i) that the amount  outstanding at any time
                           of  any  Indebtedness   issued  with  original  issue
                           discount is the face amount of such Indebtedness less
                           the  remaining  unamortized  portion of the  original
                           issue discount of such  Indebtedness  at such time as
                           determined  in  conformity  with  GAAP and (ii)  that
                           Indebtedness  shall not  include  any  liability  for
                           federal,  state,  local or other  taxes  that are not
                           delinquent.




                                                              - 21 -












                           Notwithstanding  anything to the  contrary  contained
                           herein,  for  purposes of  calculating  the  Leverage
                           Ratio,  in the case of each of clauses (i),  (ii) and
                           (iii) above, the amount of such Indebtedness shall be
                           the amount that would  appear as a  liability  on the
                           balance  sheet of such Person  prepared in accordance
                           with GAAP.
Interest Rate
                           Agreement: any interest rate swap agreement, interest
                           rate cap agreement, interest rate collar agreement or
                           other similar  agreement or  arrangement  designed to
                           protect  Borrower,  Parent or any of their respective
                           Subsidiaries against fluctuations in interest rates.

Ion
Acquisition:     the acquisition by Borrower of certain of the assets of Ion
                 Leasing, Inc. pursuant to the Ion Acquisition Documents.

Ion
Acquisition
                           Documents:
                   collectively,  the  Asset  Purchase  Agreement  dated  as  of
                           September  24, 1993 among  Borrower  and Ion Leasing,
                           Inc. and its  shareholders,  and all other documents,
                           agreements  or  certificates  executed in  connection
                           therewith.

Leverage
                           Ratio:  the  ratio  of (i) the  aggregate  amount  of
                           Indebtedness  of  the  Borrower,   Parent  and  their
                           respective    Subsidiaries   to   (ii)   four   times
                           Consolidated   EBITDA  for  the  most  recent  fiscal
                           quarter for which  financial  information  in respect
                           thereof  is   available.   In  making  the  foregoing
                           calculation,  (A) pro forma  effect shall be given to
                           (1) any Indebtedness  incurred  subsequent to the end
                           of  the   applicable   period  to  the  extent   such
                           Indebtedness   is   outstanding   at  the   date   of
                           calculation, and (2) any Indebtedness incurred during
                           such  period  to  the  extend  such  Indebtedness  is
                           outstanding  at the date of  calculation  and (3) any
                           Indebtedness to be incurred,  in each case as if such
                           Indebtedness  had been  incurred  on the first day of
                           such period and after  giving pro forma effect to the
                           application  of  the  proceeds  thereof  as  if  such
                           application  had  occurred  on such  first  day;  (B)
                           interest  expense  attributable  to  interest  on any
                           Indebtedness




                                                              - 22 -














                           (whether  existing or being  incurred)  computed on a
                           pro forma basis and bearing a floating  interest rate
                           shall be  computed  as if the rate in  effect  on the
                           date of calculation (taking into account any Interest
                           Rate  Agreement  applicable to such  Indebtedness  if
                           such Interest Rate  Agreement has a remaining term in
                           excess of 12 months) had been the applicable rate for
                           the entire  period;  (C) there shall be excluded from
                           Interest  Expense any Interest Expense related to any
                           amount of Indebtedness  that was  outstanding  during
                           such period or thereafter but that is not outstanding
                           or is to be  repaid on the date of  calculation;  (D)
                           pro forma effect shall be given to Asset Dispositions
                           and any  asset  acquisitions  (including  giving  pro
                           forma  effect to the  application  of proceeds of any
                           Asset  Disposition)  that occur during such period or
                           thereafter and on or prior to the date of calculation
                           as if they had  occurred  and such  proceeds had been
                           applied  on the  first day of such  period;  (E) with
                           respect to any such  period  commencing  prior to the
                           Closing  Date,  any Advances  shall be deemed to have
                           taken place on the first day of such period;  and (F)
                           pro forma effect shall be given to Asset  Disposition
                           and asset  acquisitions  (including  giving pro forma
                           effect to the  application  of  proceeds of any Asset
                           Disposition)  that have been made by any Person  that
                           has become a Subsidiary  of Parent or Borrower or has
                           been merged with or into  Borrower,  Parent or any of
                           their  Subsidiaries  during such period or subsequent
                           to such period and prior to date of  calculation  and
                           that would have  constituted  Asset  Dispositions  or
                           asset  acquisitions  had such  transactions  occurred
                           when  such  Person  was a  Subsidiary  of  Parent  or
                           Borrower  as  if  such  Asset  Depositions  or  asset
                           acquisitions   were  Asset   Dispositions   or  asset
                           acquisitions  that  occurred on the first day of such
                           Period.

                           LIBOR Rate: the rate (rounded upwards,  if necessary,
                           to the nearest  1/16th of 1 percent) at which  dollar
                           deposits  in same day funds would be offered at 11:00
                           a.m.,  London  time two  Business  Days  prior to the
                           commencement of the relevant interest period by major
                           banks in the  London  eurodollar  market for a period
                           comparable  to  the  relevant   interest  period,  as
                           obtained from Chase Manhattan Bank.





                                                              - 23 -












LIBOR Rate
Advance:             an Advance bearing an interest rate based on the LIBOR
                     Rate.

                     Lien: any lien, mortgage, pledge, security interest,
                     charge or encumbrance of any kind, whether voluntary or
                     involuntary, (including any conditional sale or other title
                     retention agreement, any lease in the nature thereof, and
                     any agreement to give any security interest.
Loan
                           Documents:
                  this     agreement,  the Note, the Pledge Agreement,  Parental
                           Guaranty,  and all other  instruments,  documents and
                           agreements  executed  by or on  behalf  of  Borrower,
                           Parent or any of their  respective  Subsidiaries  and
                           delivered   concurrently  herewith  or  at  any  time
                           hereafter   to  or  for  the  benefit  of  Lender  in
                           connection  with the Advances and other  transactions
                           contemplated  by  this  agreement,  all  as  amended,
                           supplemented or modified from time to time.

Material
Adverse
Change:          (a) a material adverse change in the business, assets,
                  prospects, operations or condition, financial or otherwise,
                  of the Borrower, Parent, or their respective Subsidiaries or
                 (b) material impairment of the ability of the Borrower to
                  perform its obligations under this letter agreement.

                           Maturity Date:   364 days from the date hereof.

                           MRR: monthly recurring alarm monitoring and extended
                           service plan revenues from services provided under
                           Subscriber Accounts, including patrol revenues.

                           Net Income:  for any period, the net income (or loss)
                           of Borrower, Parent and their respective Subsidiaries
                           on  a  consolidated  basis  after  provision  for  or
                           benefit from income and franchise taxes determined in
                           accordance  with GAAP, but excluding:  (a) the income
                           (or loss) of any Person  (other than Borrower and its
                           wholly-owned  Subsidiaries) in which Borrower, Parent
                           or  any  of  their  respective  Subsidiaries  has  an
                           ownership   interest  unless  received  by  Borrower,
                           Parent or any of their




                                                              - 24 -














                           respective  Subsidiaries in a cash distribution;  and
                           (b) the income (or loss) of any Person  accrued prior
                           to the date it became a  wholly-owned  Subsidiary  of
                           Borrower,   Parent   or  any  of   their   respective
                           Subsidiaries or is merged into or  consolidated  with
                           Borrower,   Parent   or  any  of   their   respective
                           Subsidiaries  or such Person's assets are acquired by
                           Borrower,   Parent   or  any  of   their   respective
                           Subsidiaries.

                           Net  Proceeds:  cash  proceeds  (including  insurance
                           proceeds)  received  by  Borrower,  Parent  or any of
                           their   respective   Subsidiaries   from  any   Asset
                           Disposition  (including payments under notes or other
                           debt securities received in connection with any Asset
                           Disposition  and  insurance  proceeds  and  awards of
                           condemnation but excluding  proceeds  permitted under
                           this  agreement to be used for  replacement  assets),
                           net of (a) the costs of such sale, lease, transfer or
                           other  disposition  (including taxes  attributable to
                           such sale lease or transfer); and (b) amounts applied
                           to   repayment  of   Indebtedness   (other  than  the
                           Obligations)  secured  by a  Lien  on  the  asset  or
                           property disposed.

                           Obligations:   all   obligations,   liabilities   and
                           indebtedness of every nature of Borrower,  Parent and
                           their respective  Subsidiaries from time to time owed
                           to  Lender  under  this   agreement   including   the
                           principal   amount   of   all   debts,   claims   and
                           indebtedness,  accrued  and unpaid  interest  and all
                           fees, costs and expenses, whether primary, secondary,
                           direct, contingent,  fixed or otherwise,  heretofore,
                           now and/or from time to time hereafter  owing, due or
                           payable  whether  before  or after  the  filing  of a
                           proceeding  under the  Bankruptcy  Code by or against
                           either  Borrower,  Parent or any of their  respective
                           Subsidiaries.

                           Parent's
                           Warrant
                           Agreement:  collectively,  (a) that  certain  Warrant
                           Agreement  dated the November 3, 1993 between  Parent
                           and  United  States  Trust  Company  of New York,  as
                           Warrant Agent and (b) that certain Warrant  Agreement
                           dated May 17, 1995  between  Parent and State  Street
                           Bank and Trust Company, a successor to the
                           First National Bank of Boston, as Warrant Agent.





                                                              - 25 -












Parent's Warrants:
the warrants to purchase Parent's common stock pursuant to the Parent's Warrant
Agreement.

                           PBGC: the Pension Benefit Guaranty Corporation or any
                           successor thereto established under ERISA.

                           Permitted
                           Encumbrances: (a) Liens (other than Liens relating to
                           environmental claims or ERISA) for taxes, assessments
                           or  other  governmental   charges  not  yet  due  and
                           payable; (b) statutory Liens of landlords,  carriers,
                           warehousemen,   mechanics,   materialmen   and  other
                           similar liens  imposed by law,  which are incurred in
                           the  ordinary  course of  business  for sums not more
                           than 30 days  delinquent or which are being contested
                           in good  faith;  provided  that a  reserve  or  other
                           appropriate  provision shall have been made therefor;
                           (c)  Liens  (other  than any Lien  imposed  by ERISA)
                           incurred or deposits  made in the ordinary  course of
                           business in connection  with  workers'  compensation,
                           unemployment  insurance  and  other  types of  social
                           security,  or to secure the  performance  of tenders,
                           statutory  obligations,  surety,  stay,  customs  and
                           appeal bonds,  bids,  leases,  government  contracts,
                           trade  contracts,   performance  and  return-of-money
                           bonds and other  similar  obligations  (exclusive  of
                           obligations for the payment of borrowed  money);  (d)
                           deposits,  in  an  aggregate  amount  not  to  exceed
                           $200,000,  made in the ordinary course of business to
                           secure  real  property  leases  and/or  liability  to
                           insurance  carriers;  (e)  Liens for  purchase  money
                           obligations;  provided  that: (i) the purchase of the
                           asset  subject  to any such Lien is  permitted  under
                           this agreement;  (ii) the Indebtedness secured by any
                           such Lien is  permitted  under  this  agreement;  and
                           (iii)  any such  Lien  encumbers  only  the  asset so
                           purchased;  (f) any  attachment  or judgment Lien not
                           constituting   an  Event  of   Default   under   this
                           agreement;  (g) leases or subleases granted to others
                           not  interfering  in any  material  respect  with the
                           business  of   Borrower,   Parent  or  any  of  their
                           respective      Subsidiaries;      (h)     easements,
                           rights-of-way,   restrictions,   and  other   similar
                           charges  or  encumbrances   not  interfering  in  any
                           material  respect  with the  ordinary  conduct of the
                           business of Borrower, Parent or




                                                              - 26 -














                           any  of  their  respective   Subsidiaries;   (i)  any
                           interest or title of a lessor or sublessor  under any
                           lease permitted by this agreement;  (j) Liens arising
                           from filing UCC financing statements regarding leases
                           permitted  by this  agreement;  (k) Liens in favor of
                           Lender or on behalf of Lender;  (l) Liens in favor of
                           Ion Leasing,  Inc. to the extent such Liens  encumber
                           only the cash (and any investment  contracts and life
                           insurance policies purchased  therewith) deposited by
                           Borrower in a segregated trust account to defease the
                           promissory  note  issued by  Borrower  to Ion Leasing
                           Inc.   in   accordance   with  the  Ion   Acquisition
                           Documents;  and (m) Liens existing on the date hereof
                           and renewals and extensions thereof,  which Liens are
                           set forth on Schedule A to this agreement.

                           Person:   includes  natural  persons,   corporations,
                           limited liability  companies,  limited  partnerships,
                           general  partnerships,  joint stock companies,  joint
                           ventures,  associations,  companies,  trusts,  banks,
                           trust  companies,  land  trusts,  business  trusts or
                           other  organizations,  whether or not legal entities,
                           and    governments   and   agencies   and   political
                           subdivisions  thereof and their respective  permitted
                           successors   and   assigns  (or  in  the  case  of  a
                           governmental   person,   the   successor   functional
                           equivalent of such Person).

                           Plan:any employee pension plan of Borrower, Parent or
                           any of their Subsidiaries subject to ERISA.

Redeemable
                           Stock:  means any class or series of Capital Stock of
                           any  Person  that by its  terms or  otherwise  is (i)
                           required to be redeemed  prior to the Maturity  Date,
                           (ii)  redeemable  at the option of the holder of such
                           class of series of Capital Stock at any time prior to
                           the  Maturity  Date  or  (iii)  convertible  into  or
                           exchangeable  for Capital Stock referred to in clause
                           (i) or (ii) above or Indebtedness  having a scheduled
                           maturity prior to the Maturity Date.

Related




                                                              - 27 -












Transactions:    the execution and delivery of the Loan Documents, each
                 Advance on the Closing Date and the payment of all fees,
                 costs and expenses associated with all of the foregoing.

Subordinated
Discount Note
                           Documents:
                 the       Subordinated  Discount Note Placement Agreement,  the
                           Subordinated    Discount    Note    Indenture,    the
                           Subordinated  Discount  Notes,  and all  instruments,
                           documents  and  agreements  executed  pursuant to the
                           terms of the foregoing.

Subordinated
Discount Note
Indenture:          the Indenture dated as of May 17, 1995 by and among
                    State Street Bank and Trust Company, as successor to The
                    First National Bank of Boston, as trustee, Parent and
                    Borrower with respect to the Subordinated Discount Notes.

Subordinated
Discount Note
Placement
                           Agreement:
  the Placement Agreement among Parent, Borrower and Morgan Stanley and Co. and
  Montgomery Securities with respect to the issuance and sale
  of the Subordinated Discount Notes and the Parent warrants.

Subordinated
Discount
                           Notes: those Senior  Subordinated  Discount Notes Due
                           2005 of  Borrower  issued  on May 17,  1995,  and the
                           substantially identical subordinated notes registered
                           under the Securities Act of 1933 which were issued in
                           exchange  for  such  initial  Subordinated   Discount
                           Notes, as contemplated by the  Subordinated  Discount
                           Note Documents.

Subscriber
                 Accounts:  alarm monitoring accounts or alarm services accounts
                    of customers arising under written contracts with such
                    customers pursuant to which Borrower, Parent or any of their
                    respective Subsidiaries provides alarm monitoring or other




                                                              - 28 -














                      security services or sells, installs and services security
                      alarm systems.

                           Subsidiary:   with   respect  to  any   Person,   any
                           corporation,   partnership   association   or   other
                           business  entity of which  more than 50% of the total
                           voting  power  of  shares  of  stock  (or  equivalent
                           ownership or controlling  interest) entitled (without
                           regard to the occurrence of any  contingency) to vote
                           in the  election of  directors,  managers or trustees
                           thereof is at the time owned or controlled,  directly
                           or  indirectly,  by that Person or one or more of the
                           other  Subsidiaries  of that Person or a  combination
                           thereof.

                           Term: with respect to a WIBOR Advance,  the number of
                           days  between the date of such WIBOR  Advance and the
                           expiration date thereof,  as selected by Borrower and
                           agreed  to  by  Lender,   but,  unless  Lender  shall
                           otherwise agree, not in excess of 90 days.

Trade Payables:            means,     with respect to any Person,  any accounts
                           payables or any other  indebtedness  or  monetary
                           obligation  to trade  creditors  created,  assumed or
                           Guaranteed by
                           such Person or any of its Subsidiaries arising in the
                           ordinary  course of business in  connection  with the
                           acquisition of goods or services.

Transition Costs:          the costs and expenses  incurred by  Borrower, Parent
                           or any of their respective  Subsidiaries in the
                           ordinary course of business  and  capitalized  as
                           acquisition costs  in   connection   with  converting
                           acquired Subscriber   Accounts  to   Subscriber
                           Accounts  of Borrower, Parent or any of their
                           respective Subsidiaries.

Westar Security: Westar Security, Inc., a wholly-owned subsidiary of
                 Parent
                 WestSec: WestSec, Inc., a wholly-owned subsidiary of Borrower.





                                                              - 29 -












                       WIBOR
                       Rate:   the fixed rate of interest offered by the Lender
                               on a WIBOR Advance.

                       WIBOR
                       Advance: an Advance bearing an interest rate based on the
                               WIBOR Rate.






                                                              - 30 -