EXHIBIT 4.13
                                  8% DEBENTURE

$__________                                                    January  __, 2007

               FOR  VALUE  RECEIVED,   Intraop  Medical  Corporation,  a  Nevada
corporation  (the  "MAKER"),  with its  primary  offices  located at 570 Del Rey
Avenue,   Sunnyvale,   California   94085  promises  to  pay  to  the  order  of
_____________, or its registered assigns (the "PAYEE"), upon the terms set forth
below, the principal sum of ______________  Dollars  ($_______) plus interest on
the  unpaid  principal  sum  outstanding  at  the  rate  of 8%  per  annum  (the
"DEBENTURE").  This  Debenture  is issued  pursuant to the  Securities  Purchase
Agreement, dated as of January __, 2007 (the "PURCHASE AGREEMENT"),  and defined
terms used herein but not defined  herein shall have the meanings  given to such
terms in the Purchase Agreement.

1. PAYMENTS.

         (a) The full  amount of  principal  and  accrued  interest  under  this
         Debenture shall be due on April __, 2007 (the "MATURITY DATE"),  unless
         due earlier in accordance with the terms of this Debenture.

         (b)  Maker  may  prepay,  in whole or in part,  the  principal  sum and
         interest  under this  Debenture  without the prior  written  consent of
         Payee.

2. EVENTS OF DEFAULT.

         (a) "EVENT OF  DEFAULT",  wherever  used  herein,  means any one of the
         following events (whatever the reason and whether it shall be voluntary
         or  involuntary  or  effected  by  operation  of law or pursuant to any
         judgment,  decree  or  order  of any  court,  or  any  order,  rule  or
         regulation of any administrative or governmental body):

                  (i) any failure to pay the  principal  of, or the interest on,
                  this  Debenture,  as and when the same  shall  become  due and
                  payable;

                  (ii) Maker shall fail to observe or perform any  obligation or
                  shall breach any term or provision of this  Debenture and such
                  failure  or  breach  shall  not have  been  remedied  within 5
                  calendar  days after the date on which  notice of such failure
                  or breach shall have been delivered;

                  (iii) Maker or any of its  Subsidiaries  shall fail to observe
                  or perform any of their  respective  obligations owed to Payee
                  or any other covenant,  agreement,  representation or warranty
                  contained in, or otherwise  commit any breach hereunder or in,
                  the Purchase  Agreement  or the  Transaction  Documents  which
                  failure is not cured, if possible to cure,  within the earlier
                  to occur of (A) 15 business  days after notice of such default
                  sent by the Payee  and (B) 20  business  days  after the Maker
                  shall become or should have become aware of such failure;
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                  (iv) Maker or any of its Subsidiaries shall commence, or there
                  shall be commenced  against  Maker or any  Subsidiary,  a case
                  under any applicable  bankruptcy or insolvency  laws as now or
                  hereafter in effect or any successor thereto,  or Maker or any
                  Subsidiary   commences   any   other   proceeding   under  any
                  reorganization,  arrangement,  adjustment  of debt,  relief of
                  debtors, dissolution, insolvency or liquidation or similar law
                  of  any  jurisdiction  whether  now  or  hereafter  in  effect
                  relating  to Maker or any  Subsidiary,  or there is  commenced
                  against  Maker  or  any   Subsidiary   any  such   bankruptcy,
                  insolvency or other proceeding which remains undismissed for a
                  period of 60 days; or Maker or any  Subsidiary is  adjudicated
                  insolvent or  bankrupt;  or any order of relief or other order
                  approving any such case or proceeding is entered;  or Maker or
                  any Subsidiary suffers any appointment of any custodian or the
                  like  for it or any  substantial  part of its  property  which
                  continues undischarged or unstayed for a period of 60 days; or
                  Maker or any  Subsidiary  makes a general  assignment  for the
                  benefit of creditors; or Maker or any Subsidiary shall fail to
                  pay,  or shall  state  that it is unable  to pay,  or shall be
                  unable to pay,  its debts  generally  as they  become  due; or
                  Maker or any Subsidiary  shall call a meeting of its creditors
                  with  a  view  to  arranging  a  composition,   adjustment  or
                  restructuring  of its debts; or Maker or any Subsidiary  shall
                  by any act or failure to act  expressly  indicate  its consent
                  to, approval of or  acquiescence  in any of the foregoing;  or
                  any  corporate  or  other  action  is  taken  by  Maker or any
                  Subsidiary for the purpose of effecting any of the foregoing;

                  (v)  Maker  or  any  Subsidiary  shall  default  in any of its
                  respective  obligations  under any other note or any mortgage,
                  credit  agreement  or  other  facility,  indenture  agreement,
                  factoring  agreement or other instrument under which there may
                  be issued,  or by which there may be secured or evidenced  any
                  indebtedness  for  borrowed  money or money due under any long
                  term  leasing  or  factoring   arrangement  of  Maker  or  any
                  Subsidiary  in an  amount  exceeding  $150,000,  whether  such
                  indebtedness now exists or shall hereafter be created and such
                  default  shall result in such  indebtedness  becoming or being
                  declared  due and payable  prior to the date on which it would
                  otherwise become due and payable;

                  (vi)  Maker  shall  (a) be a party to any  Change  of  Control
                  Transaction  (as defined below) unless directly as a result of
                  the issuance of securities  pursuant to the Purchase Agreement
                  or any other  agreement for  securities  pursuant to which the
                  Payee was a  participant,  (b) agree to sell or dispose all or
                  in  excess of 33% of its  assets  in one or more  transactions
                  (whether or not such sale would constitute a Change of Control
                  Transaction),  (c) redeem or repurchase more than a DE MINIMIS


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                  number of shares of Common Stock or other equity securities of
                  Maker,  or (d) make any  distribution  or  declare  or pay any
                  dividends (in cash or other property, other than common stock)
                  on, or  purchase,  acquire,  redeem,  or retire any of Maker's
                  capital  stock,  of  any  class,   whether  now  or  hereafter
                  outstanding.   "CHANGE  OF  CONTROL   TRANSACTION"  means  the
                  occurrence  after the date hereof of any of (i) an acquisition
                  after the date  hereof  by an  individual  or legal  entity or
                  "group" (as described in Rule  13d-5(b)(1)  promulgated  under
                  the Securities  Exchange Act of 1934, as amended) of effective
                  control  (whether  through  legal or  beneficial  ownership of
                  capital  stock of the Maker,  by contract or  otherwise) of in
                  excess of 33% of the  voting  securities  of the Maker  (other
                  than by means of exercise of the Warrants),  or (ii) the Maker
                  merges  into or  consolidates  with any other  Person,  or any
                  Person merges into or  consolidates  with the Maker and, after
                  giving effect to such  transaction,  the  stockholders  of the
                  Maker  immediately prior to such transaction own less than 66%
                  of the  aggregate  voting power of the Maker or the  successor
                  entity  of such  transaction,  or  (iii)  the  Maker  sells or
                  transfers  all or  substantially  all of its assets to another
                  Person and the stockholders of the Maker  immediately prior to
                  such  transaction  own less than 66% of the  aggregate  voting
                  power  of  the   acquiring   entity   immediately   after  the
                  transaction,  or (iv) a  replacement  at one time or  within a
                  three year period of more than  one-half of the members of the
                  Maker's board of directors which is not approved by a majority
                  of those individuals who are members of the board of directors
                  on the date hereof (or by those individuals who are serving as
                  members of the board of directors on any date whose nomination
                  to the board of  directors  was  approved by a majority of the
                  members of the board of directors  who are members on the date
                  hereof),  or (v) the execution by the Maker of an agreement to
                  which the Maker is a party or by which it is bound,  providing
                  for any of the events set forth in clauses  (i)  through  (iv)
                  above; or

                  (vii) Maker shall unreasonably  modify or change its method of
                  accounting or enter into,  modify,  or terminate any agreement
                  currently existing, or at any time hereafter entered into with
                  any third  party  accounting  firm or  service  bureau for the
                  preparation or storage of its accounting  records,  or restate
                  or modify  its  financial  statements  for any  period of time
                  prior to the date of this Debenture.

         (b) If any Event of Default occurs,  the full principal  amount of this
         Debenture, together with all accrued interest thereon, shall become, at
         the Payee's election, immediately due and payable in cash. Commencing 5
         calendar days after the occurrence of any Event of Default that results
         in the  acceleration  of  this  Debenture,  the  interest  rate on this
         Debenture  shall  accrue at the rate of 18% per  annum,  or such  lower
         maximum  amount of interest  permitted to be charged  under  applicable
         law.  The  Payee  need  not  provide,  and  Maker  hereby  waives,  any
         presentment, demand, protest or other notice of any kind, and the Payee
         may immediately and without  expiration of any grace period enforce any
         and all of its rights and  remedies  hereunder  and all other  remedies
         available to it under applicable law. Such declaration may be rescinded
         and annulled by Payee at any time prior to payment  hereunder.  No such
         rescission or annulment shall affect any subsequent Event of Default or
         impair any right consequent thereon.

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3. NO WAIVER OF PAYEE'S RIGHTS.  All payments of principal and interest shall be
made without setoff, deduction or counterclaim.  No delay or failure on the part
of the Payee in exercising any of its options, powers or rights, nor any partial
or single  exercise of its options,  powers or rights shall  constitute a waiver
thereof or of any other option, power or right, and no waiver on the part of the
Payee of any of its options,  powers or rights shall  constitute a waiver of any
other  option,  power or right.  Maker  hereby  waives  presentment  of payment,
protest, and all notices or demands in connection with the delivery, acceptance,
performance,  default or endorsement of this Debenture.  Acceptance by the Payee
of less than the full amount due and payable hereunder shall in no way limit the
right of the Payee to require full payment of all sums due and payable hereunder
in accordance with the terms hereof.

4. MODIFICATIONS. No term or provision contained herein may be modified, amended
or waived except by written agreement or consent signed by the party to be bound
thereby.

5.  CUMULATIVE  RIGHTS AND  REMEDIES;  USURY.  The rights and  remedies of Payee
expressed  herein are  cumulative  and not  exclusive of any rights and remedies
otherwise available under the Transaction Documents or applicable law (including
at equity).  The election of Payee to avail  itself of any one or more  remedies
shall not be a bar to any other available remedies, which Maker agrees Payee may
take from time to time.  If it shall be found that any  interest  due  hereunder
shall violate  applicable laws governing  usury, the applicable rate of interest
due hereunder  shall be reduced to the maximum  permitted rate of interest under
such law.

6.  COLLECTION  EXPENSES.  If Payee shall  commence an action or  proceeding  to
enforce  this  Debenture,  then  Maker  shall  reimburse  Payee for its costs of
collection  and  reasonable  attorneys  fees  incurred  with the  investigation,
preparation and prosecution of such action or proceeding.

7.  SEVERABILITY.  If any provision of this  Debenture is declared by a court of
competent jurisdiction to be in any way invalid,  illegal or unenforceable,  the
balance of this  Debenture  shall  remain in  effect,  and if any  provision  is
inapplicable  to any  person  or  circumstance,  it  shall  nevertheless  remain
applicable to all other persons and circumstances. If it shall be found that any
interest or other amount deemed interest due hereunder shall violate  applicable
laws  governing  usury,  the  applicable  rate of interest due  hereunder  shall
automatically be lowered to equal the maximum permitted rate of interest.

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<PAGE>

8.  SUCCESSORS AND ASSIGNS.  This Debenture  shall be binding upon Maker and its
successors  and shall inure to the benefit of the Payee and its  successors  and
assigns.  The term  "Payee" as used  herein,  shall also  include any  endorsee,
assignee or other holder of this Debenture.

9. LOST OR STOLEN  PROMISSORY  DEBENTURE.  If this  Debenture  is lost,  stolen,
mutilated or otherwise destroyed, Maker shall execute and deliver to the Payee a
new promissory  note  containing  the same terms,  and in the same form, as this
Debenture.  In such  event,  Maker may  require the Payee to deliver to Maker an
affidavit of lost  instrument  and customary  indemnity in respect  thereof as a
condition to the delivery of any such new promissory note.

10. DUE  AUTHORIZATION.  This Debenture has been duly  authorized,  executed and
delivered by Maker and is the legal  obligation  of Maker,  enforceable  against
Maker in  accordance  with its  terms.  No  consent  of any  other  party and no
consent,  license,  approval or authorization of, or registration or declaration
with,  any  governmental  authority,  bureau or agency is required in connection
with the execution,  delivery or  performance  by the Maker,  or the validity or
enforceability  of this Debenture  other than such as have been met or obtained.
The  execution,  delivery  and  performance  of this  Debenture  and  all  other
agreements  and  instruments  executed  and  delivered  or  to be  executed  and
delivered pursuant hereto or thereto or the securities  issuable upon conversion
of this will not violate any  provision of any existing law or regulation or any
order or decree of any court,  regulatory body or  administrative  agency or the
certificate of incorporation or by-laws of the Maker or any mortgage, indenture,
contract or other  agreement to which the Maker is a party or by which the Maker
or any property or assets of the Maker may be bound.

11.  GOVERNING  LAW.  All  questions  concerning  the  construction,   validity,
enforcement  and  interpretation  of this  Debenture  shall be  governed  by and
construed and enforced in accordance  with the internal laws of the State of New
York,  without  regard to the  principles of conflict of laws  thereof.  Each of
Maker and Payee agree that all legal proceedings concerning the interpretations,
enforcement  and defense of this  Debenture  shall be commenced in the state and
federal courts  sitting in the City of New York,  Borough of Manhattan (the "NEW
YORK  COURTS").  Each of  Maker  and  Payee  hereby  irrevocably  submit  to the
exclusive  jurisdiction  of the New  York  Courts  for the  adjudication  of any
dispute  hereunder  (including the  enforcement of this  Debenture),  and hereby
irrevocably  waives, and agrees not to assert in any suit, action or proceeding,
any claim  that it is not  personally  subject to the  jurisdiction  of any such
court, that such suit, action or proceeding is improper. Each of Maker and Payee
hereby  irrevocably  waive  personal  service of process and consents to process
being served in any such suit,  action or  proceeding  by mailing a copy thereof
via  registered  or  certified  mail or  overnight  delivery  (with  evidence of
delivery)  to the other at the  address in effect  for  notices to it under this
Debenture  and agrees that such service  shall  constitute  good and  sufficient
service of process and notice thereof.  Nothing contained herein shall be deemed
to limit in any way any right to serve  process in any manner  permitted by law.
Each of  Maker  and  Payee  hereby  irrevocably  waive,  to the  fullest  extent
permitted  by  applicable  law,  any and all right to trial by jury in any legal
proceeding  arising  out of or relating to this  Debenture  or the  transactions
contemplated hereby.

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<PAGE>

12.  NOTICE.  Any and all notices or other  communications  or  deliveries to be
provided by the Payee hereunder shall be in writing and delivered personally, by
facsimile,  sent by a nationally recognized overnight courier service or sent by
certified or registered mail, postage prepaid, addressed to the Maker at 570 Del
Rey Avenue,  Sunnyvale,  California  94085,  facsimile  number:  (408) 636-0022,
Attention:  Donald A. Goer,  Chief Executive  Officer,  or such other address or
facsimile  number as the Maker may  specify  for such  purposes by notice to the
Payee delivered in accordance with this paragraph.  Any and all notices or other
communications  or deliveries to be provided by the Maker  hereunder shall be in
writing and delivered personally,  by facsimile, sent by a nationally recognized
overnight  courier  service or sent by certified  or  registered  mail,  postage
prepaid,  addressed  to the  Payee  at  _________,  facsimile  number:  _______,
Attention:  _______,  or such other address or facsimile number as the Payee may
specify for such purposes by notice to the Maker  delivered in  accordance  with
this paragraph.  Any notice or other communication or deliveries hereunder shall
be deemed given and effective on the earliest of (i) the date of transmission if
delivered  by hand or by telecopy  that has been  confirmed  as received by 5:00
p.m.  (New York City time) on a business  day, (ii) one business day after being
sent by nationally  recognized  overnight  courier or received by telecopy after
5:00 p.m.  (New York City time) on any day, or (iii) 5 business days after being
sent by  certified  or  registered  mail,  postage and charges  prepaid,  return
receipt requested.

     The  undersigned  signs  this  Debenture  as a maker and not as a surety or
guarantor or in any other capacity.



                                  INTRAOP MEDICAL CORPORATION

                                             By:  _____________________
                                             Name:
                                             Title:

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