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                                                                    Exhibit 10.4


                       ASIA IT CAPITAL INVESTMENT LIMITED
                       4 Etage, 15 rue de la Confederation
                                   1204 Geneva
                                   Switzerland

                              Tel: +41 22 318 00 90
                              Fax: +4122 318 00 95

                                                                20 November 2001




Medicsight Limited
46 Berkeley Square
London W1 J 5AT
England

For the attention of Mr S Allesch-Taylor

This letter sets out the terms and conditions on which we are prepared to offer
a cash advance facility in pounds sterling:

1.       INTERPRETATION

In this letter:

"Amount Drawn Down"               MEANS the amount of each advance requested by
                                  you on each occasion you give notice
                                  requesting an advance in accordance with
                                  clause 3.2

"Facility"                        MEANS the sum of El 0,000,000

"Facility Letter"                 MEANS the agreement constituted by this letter
                                  and your acceptance

"Repayment Date"                  MEANS 20 November 2004

"Security"                        MEANS a second fixed charge on all your shares
                                  and other securities and all land and
                                  buildings and a second floating charge on all
                                  your other assets In the form contained in the
                                  Security Documents

"Security Documents"              MEANS a Loan Stock Instrument in the form
                                  attached to this Facility Letter

"Termination Date"                MEANS the Repayment Date or, if earlier, the
                                  date on which the Facility is cancelled under
                                  clause 7



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2.       CONDITIONS PRECEDENT

         The Facility shall be made available to you when we have received in
         form and substance satisfactory to us,

2.1      the duplicate of this Facility Letter with the attached acceptance,
         duly signed by you;

2.2      budget estimates for the period during which the Facility may be drawn
         down; and

2.3      a copy of the Security Documents duly executed by you.

3.       ADVANCES

3.1      Subject to the terms of this Facility Letter, the Facility shall be
         available to you until the Termination Date.

3.2      Notice requesting an advance must be received by us no later than noon
         (London time) two days before the date on which the advance is
         required. The notice must specify the amount of the advance required.

3.3      Unless we specifically agree, you may not request an advance more than
         once each month.

3.4      You must supply a copy of your management accounts with each request
         for an advance; such management accounts must show that expenditure is
         not more than 110 per cent of budgeted estimates, plus the amount of
         any Income in excess of budgeted income or less the amount of any
         income under budgeted income (other than loans, advances and share
         capital Issues and expenses relating to share capital issues).

3.5      We shall have no obligation to make any advance if:

3.5.1    the management accounts delivered pursuant to clause 3.4 show
         expenditure more than 110 per cent of budgeted estimates (adjusted as
         provided In 3.4 above), but this shall not preclude us from advancing
         part of the Facility if we think fit, and if we do so on one occasion
         we shall not be committed to do so on any other occasion;

3.5.2    the representations, warranties and/or undertakings in clause 6 shall
         not be true and correct; or

3.5.3    any event of default under clause 7 has occurred and is continuing.



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4.       INTEREST AND REPAYMENT

4.1      Interest shall be charged on the Facility at an annual rate 2% above
         the London Inter-Bank Offered Rate for Sterling of an amount equal to
         the Amount Drawn Down (or if quotations cannot readily be obtained for
         the Amount Drawn Down, the average of the amounts for which quotations
         can be readily obtained higher and lower than the Amount Drawn Down) at
         11.00 am London time on the date of this Facility Letter for a period
         of one year (or if quotations for a period of one year are not
         available, for the longest period that is less than one year) and a
         certificate from Barclays Bank Pic (or any other bank selected by you)
         as to the rates offered to that bank shall be conclusive and binding on
         you and us.

4.2      Interest will be calculated on a daily basis in arrears on the basis of
         a 365 day year and, unless the Facility is converted by us into
         ordinary shares in accordance with the terms of the Security Documents,
         shall be payable on the Repayment Date.

4.3      Unless the Facility is converted by us into ordinary shares in
         accordance with the terms of the Security Documents, you. shall repay
         the Facility on the Repayment Date.

4.4      Subject to the provisions of the Security Documents, you may repay the
         Facility, in whole or in part, at any time on giving not less than [one
         month's) notice.

5.       PAYMENTS

5.1      All payments to be made by you under this Facility Letter shall be made
         in pounds sterling in London and in immediately available funds.

5.2      All payments to be made by you to us under this Facility Letter shall
         be made without set-off or counterclaim and free and clear without any
         deduction (save for any amount you are required to withhold in respect
         of tax on the interest payable on the Facility).

6.       REPRESENTATIONS AND WARRANTIES

6.1      You represent and warrant to us that:

         6.1.1    you have full power to enter into and perform your obligations
                  under this Facility Letter (which has been duly accepted by
                  you) and to borrow and repay up to the maximum amount of the
                  Facility and have obtained and will maintain in effect all
                  necessary corporate authorisatlons and all other necessary
                  consents, licences and authorities;

         6.1.2    acceptance of this Facility Letter and the drawing of any part
                  of the Facility does not, and will not, constitute an event of
                  default under or breach of the terms of the charge, contract,
                  undertaking or restrictions binding on you;



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         6.1.3    no event has occurred which constitutes (or with the giving of
                  notice or lapse of time or both would constitute) one of the
                  events of default specified in clause 7 below;

         6.1.4    you are not in default under any agreement to which you are a
                  party which would have a material adverse effect on your
                  financial condition; and

         6.1.5    no litigation, arbitration or proceeding is taking place,
                  pending or, to your knowledge, threatened against you or any
                  of your assets which may have a material adverse effect on
                  your assets or financial condition.

6.2      You undertake to us that you will make a public offer of ordinary
         shares to raise the sum of not less than (pound)25,000,000 (including
         the expenses of issue) no later than three months after the date any
         part of the Facility is advanced by us to you. In the event the full
         amount is not raised this facility is not compromised.

6.3      Each of your representations, warranties and undertakings shall be
         continuing and deemed to be repeated on the making of any request for
         an Amount Drawn Down

7.       EVENTS OF DEFAULT

7.1      If:

         7.1.1    default is made for more than 14 days in the payment on the
                  due date of any amount payable under the Facility;

         7.1.2    you are in materially breach of any other of your obligations
                  under this Facility for more than 30 days after written notice
                  from us to you requiring such breach to be remedied;

         7.1.3    you admit in writing your inability to pay or shall become
                  unable to pay your debts generally as they fall due, or a
                  petition is issued for your winding up, or you shall give
                  notice to creditors and/or members convening meetings to
                  consider a proposal for a Creditors Voluntary Winding up or
                  become insolvent, or file any petition for the making of an
                  Administration Order in respect of you, or for action for
                  relief under any bankruptcy, insolvency or moratorium law;

         7.1.4    proceedings are started for the appointment of a receiver,
                  trustee or similar officer of all or any of your revenues and
                  assets;

         7.1.5    a distress or other execution is levied on or against any
                  substantial part of your property and is not discharged within
                  15 days;

         7.1.6    there shall be a change in the Identity of the person who
                  exercises control (as defined in section 840 of the Income and
                  Corporation Taxes Act 1988) of you from the person who
                  exercises such control at the date hereof;



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         7.1.7    any representation or warranty made by you to us in or
                  pursuant to this Facility Letter, and which would have
                  adversely affected our decision to lend the Facility to you,
                  shall prove to have been incorrect in any material respect
                  when made (or deemed made) or, if repeated at any time
                  hereafter by reference to the facts subsisting at such time,
                  would no longer be correct in all material respects;

         7.1.8    your undertaking in clause 6.2 shall not be compiled with

         we shall immediately be entitled to declare that the Facility is
         cancelled, whereupon no further part of the Facility may be drawn
         and/or to demand the payment of the Facility together with all interest
         and other monies due under this Facility Letter, whereupon the same
         shall become immediately due and repayable without presentation,
         demand, protest or other notice whatever.

7.2      You will notify us forthwith in writing of the occurrence of any of the
         events specified in this clause 7.

8.       FEES AND EXPENSES

         You shall reimburse us on demand for any costs or expenses (including
         but not limited to legal fees) incurred by us in the enforcement of
         this Facility Letter.

9.       LAW AND JURISDICTION

9.1      This Facility Letter shall be governed by and construed in accordance
         with English law. You and we hereby irrevocably submit to the
         jurisdiction of the English courts.

9.2      The submission to jurisdiction in clause 9.1 above shall not prevent
         proceedings being brought in any other competent court.

10.      PERIOD OF OFFER

         Please confirm your acceptance of the offer in this letter `by signing
         the acceptance on the enclosed duplicate of this letter and returning
         it to us within 21 days of today's date, failing which this offer shall
         lapse

Yours faithfully
for and on behalf of Asia IT Capital Investments Limited


W. Paterson-Brown
Director



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                               Form of Acceptance

To:      Asia IT Capital Investments Limited

We hereby accept your offer of a Facility on the terms and subject to the
conditions in the Facility Letter of which a copy is attached.

Dated 20th November,    2001

for and on behalf of Medicsight Limited



/s/ S. ALLESCH-TAYLOR
S. Allesch-Taylor
Director



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BETWEEN:

(1) MEDICSIGHT LIMITED, incorporated in England and Wales under company number
4268510 whose registered office is at 46 Berkeley Square, London W1J 5AT ("the
Company"); and

(2) ASIA IT CAPITAL INVESTMENTS LIMITED incorporated in the Commonwealth of the
Bahamas under company number 11 1704B, whose registered office is at 3rd Floor,
Bolman House, King George Street, Nassau, Bahamas, whose principal trading
address is 4 Etage, 15 rue de la Confederation, 1204 Geneva, Switzerland and
whose address for service in England is care of Paul Webster, Davies Arnold
Cooper, 6-8 Bouverie Street, London EC4Y 8DD ("the Lender")

WHEREAS the Company by resolution of its board of directors passed on ______21st
November 2001 has created the (pound)10,000,000 Convertible Secured Loan Stock
to be constituted as set out in this instrument on and subject to the terms and
conditions set out in this instrument.

NOW THIS INSTRUMENT WITNESSES:

1.       DEFINITIONS AND INTERPRETATIONS

1.1      In this instrument and the recital and the appendices to this
         instrument the following words and expressions shall have the meanings
         set out opposite them:

         "Loan                    Stock" MEANS the (pound)10,000,000 convertible
                                  secured loan stock constituted by this
                                  instrument, the amount thereof for the time
                                  being outstanding or the principal moneys
                                  represented by the same as the case may
                                  require;

         "Registered Office"      MEANS the registered office for the time being
                                  of the Company; and


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         "Stockholder"            MEANS the person or persons from time to time
                                  holding the Loan Stock.

         1.1.1.   reference to any statute or statutory provision includes a
                  reference to that statute or statutory provision as amended,
                  extended or re-enacted and to any regulation, order,
                  instrument or subordinate legislation under the relevant
                  statute or statutory provision;

         1.1.2.   reference to the singular includes a reference to the plural
                  and vice versa;

         1.1.3.   reference to any recital, condition, clause, sub-clause or
                  appendix is to a recital, condition, clause, sub-clause or
                  appendix (as the case may be) of or to this instrument;

         1.1.4.   reference to any gender includes a reference to all other
                  genders; and

         1.1.5.   references to persons in this Instrument and the appendices
                  include bodies corporate, unincorporated associations and
                  partnerships and any reference to any party who is an
                  individual Is also deemed to include their respective legal
                  personal representative(s).

2.       TERMS AND CONDITIONS OF ISSUE

2.1      The Loan Stock is hereby issued subject to the terms and conditions set
         out in appendix 2.

2.2      Title

         The Loan Stock shall be held subject to and with the benefit of the
         terms and conditions set out in appendix 2 and such terms and
         conditions shall be binding on the Company and the Stockholders and all
         persons claiming through them respectively.

2.3      Loan Stock Certificate



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         Each Loan Stock Certificate shall be executed by the Company as a deed.
         Each Loan Stock Certificate shall refer to this instrument and be in
         the form or substantially in the form of appendix 1 and the legend in
         appendix 2 shall be endorsed on or attached to each such Loan Stock
         Certificate.

3.       MAXIMUM NOMINAL AMOUNT

         The maximum nominal amount of the Loan Stock shall not exceed
         E10,000,000. The Loan Stock Is secured as provided by clause 4.

4.       SECURITY

4.1      The Company charges with full title guarantee the payment and discharge
         to the Stockholder of all monies and liabilities by the Security
         Documents covenanted to be paid or discharged by the Company and of all
         other sums now or in the future intended to be secured by the Security
         Documents:

         4.1.1.   by way of fixed charge, all stocks, shares, bonds, loans, loan
                  stock and other securities of whatsoever nature of any company
                  (whether a subsidiary of the Company or not) owned by the
                  Company from time to time;

         4.1.2.   by way of fixed charge, all estates or interests in any
                  freehold and leasehold property of the Company now and in the
                  future owned by or vested in the Company, together with all
                  buildings, fixtures (including trade fixtures) and fixed plant
                  and machinery from time to time on that property;

         4.1.3.   by way of floating charge, all the Company's present and
                  future undertaking and assets, whatever and wherever including
                  (without limitation) the uncalled capital for the time being
                  of the Company and all other property and assets not subject
                  to a fixed charge under this clause 4;



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         subject to the first fixed and floating charges created by the Company
         by a Loan Stock Instrument made on ninth November 2001 between the
         Company (1) and HTTP Technology, Inc (2)

4.2      The security created by clause 4.1 shall be:

         4.2.1.   a continuing security to the Lender and the Stockholders
                  notwithstanding any settlement of account or other matter or
                  thing whatever;

         4.2.2.   attached to monies from time to time payable under this
                  instrument and the conditions which the Lender may hold now or
                  hereafter on all or any part of the property, assets and
                  undertaking of the Company; and

         4.2.3.   in addition to any rights, powers and remedies at law or in
                  equity or otherwise

4.3      Section 103 of the Law of Property Act 1925 shall not apply to the
         security created by this clause 4. The statutory power of sale shall be
         exercisable at any time after the execution of this instrument. The
         Lender shall not exercise its power of sale until payment has been
         demanded, but this provision shall not affect a purchaser or put him on
         enquiry whether such demand has been made.

5.       ENFORCEMENT

5.1      Subject to the provisions of clause 5.9, at any time after the Loan
         Stock shall have become immediately due and repayable, the Lender (to
         the exclusion of the Stockholders) may, at Its discretion, and shall on
         request in writing of Stockholders holding at least 40% of the Loan
         Stock then in issue (but subject to the Lender being indemnified to its
         satisfaction against all proceedings, claims and demands to which the
         Lender may be liable and all costs, charges and expenses which may be
         incurred by the Lender In connection therewith), and without notice
         take such proceedings against the Company as it may deem fit.



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5.2      The Lender shall be. entitled to prove in any winding up of the Company
         in respect of the principal and/or interest payable in relation to the
         Loan Stock or other monies payable under any provision of this
         instrument.

5.3      No Stockholder (other than the Lender) shall in any circumstances be
         entitled to any remedy (whether by way of action, petition or otherwise
         howsoever) for the recovery of the Loan Stock or any part of it or any
         interest, unless the Lender, having become bound to take proceedings in
         accordance with this Instrument fail to do so. In that case any
         Stockholder may, in the name of the Lender itself either take such
         proceedings against the Company or prove in the winding up of the
         Company.

5.4      At any time after the Lender shall make an declaration for the payment
         of the principal amount of the Loan Stock or any interest thereon under
         the Loan Stock conditions (or If requested to do so by the Company) the
         Lender may appoint by writing any person which expression shall include
         any substituted receiver(s) and manager(s)) of all or any part of the
         property charged by the Company by clause 4 or any assets of the
         Company from time to time representing the same

5.5      The Lender may from time to time determine the remuneration of the
         Receiver and may remove the Receiver and appoint another in his place.

5.6      The Receiver shall be the Company's agent (subject to the terms of the
         Insolvency Act 1986) and shall have all powers conferred or which may
         be conferred by the Law of Property Act 1925 and/or the Insolvency Act
         1986. The Company alone shall be responsible for his acts and omissions
         and for his remuneration.

5.7      In particular, but without limiting any general powers or the Lender's
         pow er of sale, the Receiver shall have power:

         5.7.1.   to take possession of, collect and get in all or any part of
                  the charged property and assets of the Company and for that
                  purpose to take any proceedings in the Company's name or
                  otherwise as he shall think fit;



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         5.7.2.   to take, continue or defend any proceedings and make any
                  arrangement or compromise which the Lender or the Receiver
                  shall think fit;

         5.7.3.   to appoint managers, officers and agents for any of the above
                  purposes, at such salaries as the Receiver or the Lender may
                  determine;

         5.7.4.   to do all other acts and things which he may consider to be
                  Incidental or conducive to any of the above powers.

5.8      Any monies received by the Receiver shall be applied:

         5.8.1.   first, in satisfaction of all costs, charges and expenses
                  properly Incurred and payments properly made by the Lender or
                  the Receiver and the remuneration of the Receiver; and

         5.8.2.   secondly, in accordance with the provisions of Clause 6.

5.9      No Stockholder (including the Lender, except when acting pursuant to a
         resolution of Stockholders):

         5.9.1.   ________________________________ the Security, or;

         5.9.2.   shall be entitled to vote on any resolution to exercise any
                  powers under this clause 5, or exercise any other power to
                  enforce the Security;

         if he has given notice to convert the Loan Stock (or any part thereof)
         registered in his name in to Shares of the Company pursuant to
         Condition 3 in Appendix 2

6.       APPLICATION OF MONLES

         If the Company is wound up (whether compulsorily, voluntarily or
         subject to the supervision of the Court), all amounts payable to and
         received by the Lender and payable by and received from the liquidator
         of the Company in respect of the Loan Stock by way of principal and/or
         interest or otherwise payable under any of the provisions of this
         Instrument will be received by them on trust for application:



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6.1      first, in payment or satisfaction of the costs, charges, expenses and
         liabilities incurred by the Lender (including any unpaid remuneration)
         In or about the execution of the trusts of this instrument.

6.2      secondly, In payment of interest outstanding and owing on or in respect
         of the Loan Stock; and

6.3      thirdly, as to the balance (if any) in or towards payment of the
         principal outstanding and owing on or in respect of the Loan Stock.

7.       PLACE OF PAYMENT

         All principal moneys and interest payable in respect of the Loan Stock
         shall be payable at the Registered Office.

8.       REDEMPTION

         The Company may at any time redeem the Loan Stock subject to the terms
         and conditions set out in appendix 2 at any price agreed between the
         Stockholders and the Company.

9.       COVENANT

         The Company may not create or issue any loan Stock (whether or not
         identical in all respects and forming a single series with the Loan
         Stock), or create any charge whatsoever ranking as to security in
         priority to or pari passu with the Loan Stock.

10.      LENDER'S REMUNERATION

10.1     The Company shall pay to. the Lender for its services as trustee for
         Stockholders other than the Lender (if any) of this instrument
         remuneration at such rate as shall from time to time be agreed between
         the Company and the Lender. Remuneration shall be exclusive of any
         Value Added Tax (or analogous duty) which shall be added at the
         applicable rate and paid by the Company.



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10.2     If the Lender and the Company fall to agree on the amount of the
         remuneration or the amount of any additional remuneration for duties of
         an exceptional nature or otherwise outside the scope of the normal
         duties of the Lender (as trustee for Stockholders other than the
         Lender) under this instrument, such matters shall be determined by a
         person nominated (on the application of the Lender) by the President
         for the time being of the Law Society of England and Wales. The
         expenses involved in such nomination and the fees of such person shall
         be payable by the Company. The determination of any such person shall
         be final and binding on the Company and the Lender.

10.3     The Company shall also pay or discharge all costs, charges, liabilities
         and expenses properly incurred by the Lender in relation to the
         preparation and execution of, the exercise of its powers, authorities
         and discretions, and the performance of its duties under this
         instrument Including (but not limited to) legal and travelling expenses
         and any stamp and other taxes and duties properly paid by the Lender in
         connection with any legal proceedings brought or contemplated by the
         Lender against the Company for enforcing any obligations under this
         instrument.

10.4     All costs, charges, liabilities and expenses properly incurred and
         payments properly, made by the Lender in the lawful exercise of its
         powers under this instrument and all remuneration payable to the Lender
         shall be payable by the Company on demand. Payments actually made by
         the Lender prior to the demand shall (if not paid within 3 days after
         demand and the Lender so requires) carry interest at the rate of 3% per
         annum above the London Inter-Bank Offered Rate for Sterling of an
         amount of all other cases, interest shall accrue at such rate from the
         date 30 days after the date of demand or (where the demand specifies
         that payment shall be made on an earlier date) from such earlier date.

11.      LENDER'S POWERS

         The Lender shall have all the powers conferred on trustees by the
         Trustee Act 1925 and:



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11.1     the Lender may In relation to this Instrument act on the opinion or
         advice of or information obtained from the Registrars or any lawyer,
         valuer, surveyor, banker, broker, auctioneer, accountant or other
         expert whether obtained by the Company or by the Lender or otherwise
         and shall not be responsible for any loss occasioned by so acting. Any
         such opinion, advice or information may be sent or obtained by letter,
         telemessage, facsimile or e-mail and the Lender shall not be liable for
         acting on any opinion, advice or information purporting to be conveyed
         by such means, eve n If it shall contain some error or shall not be
         authentic;

11.2     the Lender shall not be bound to take any steps to ascertain whether
         any event of default listed in the Conditions has happened;

11.3     save as otherwise expressly provided in this Instrument, the Lender
         shall, as regards all trusts, powers, authorities and discretions
         vested in it by this Instrument, have absolute and uncontrolled
         discretion as to their exercise and, provided it shall not have acted
         fraudulently, shall not be responsible for any loss, costs, damages or
         expenses that may result from the exercise or non-exercise thereof. In
         particular, the Lender shall not be bound to act (whether at the
         request or direction of the Stockholders or otherwise) under any of the
         provisions of this Instrument unless the Lender shall first be
         Indemnified to its satisfaction against all proceedings, claims and
         demands to which the Lender may become so liable and all costs, charges
         and expenses which may be so incurred by the Lender.

11.4     The Lender shall not be responsible for having acted upon any
         resolution purported to have been passed at any meeting of the
         Stockholders of which minutes have been made and signed, even though it
         may subsequently be found that there was some defect in the
         constitution of the meeting or the passing of the resolution or that,
         for any reason, the resolution was not valid or binding on the
         Stockholders;

11.5     Without prejudice to the right of indemnity by law given to Lender, the
         Lender and every attorney, manager, agent, delegate or other person
         appointed by it under this Instrument shall be Indemnified by the
         Company against all liabilities and


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         expenses properly Incurred by it or them in the execution of the powers
         and trusts of this Instrument or of any powers, authorities or
         discretions vested in it or them pursuant to this instrument. This
         indemnity shall extend to all actions, proceedings, costs, claims and
         demands in respect of any matter or thing done or omitted in relation
         to this Instrument. The Lender may in priority to any payment to the
         Stockholders retain and pay out of any monies in its hands on the
         trusts of this Instrument the amount of any such liabilities and
         expenses and also the remuneration (if any) of the Lender as provided
         in this Instrument;

11.6     The Lender may call for and shall be at liberty to accept a certificate
         signed by any two directors of the Company as sufficient evidence of
         any fact or matter on which the Lender may require to be satisfied or
         to have information or to the effect that, in the opinion of the
         persons so certifying, any particular dealing, transaction, step or
         thing is expedient. The Lender shall not be bound to call for further
         evidence and shall not be responsible for any loss occasioned by acting
         on any such certificate; and

11.7     As between itself and the Stockholders, the Lender shall have full
         power to determine all questions and doubts arising in relation to any
         of the provisions of this Instrument. Every such determination made in
         good faith (whether or not the same shall relate in whole or in part to
         the acts and proceedings of the Lender under this Instrument) shall be
         conclusive and binding on the Lender and the Stockholders.

12.      LENDER'S POWER TO DELEGATE

         Whenever it thinks fit, the Lender may delegate by power of attorney or
         otherwise, to any person or persons all or any of the trusts, powers
         and discretions vested in it by this instrument. Delegation may be made
         upon such terms and subject to such conditions including (but not
         limited to) power to sub-delegate and subject to such regulations as
         the Lender may think fit. The Lender shall not be bound to supervise,
         the proceedings or be responsible for


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         any loss incurred by reason of any misconduct or omission on the part
         of any such delegate or sub-delegate.

13.      APPOINTMENT OF AGENTS BY LENDER

         The Lender may employ and pay an agent to transact or concur in
         transacting any business and to do or concur in doing all acts required
         to be done by the Lender, including the receipt and payment of money.

14.      LENDER NOT PRECLUDED FROM ENTERING INTO CONTRACTS

         The Lender (or any director or officer of a corporation acting as
         trustee of this instrument) shall not be precluded from:

14.1     holding any office or employment with the Company or any subsidiary or
         any person associated with the Company or any subsidiary; or

14.2     underwriting or guaranteeing the subscription of or subscribing for or
         otherwise acquiring, holding or dealing with the whole or any part of
         the Loan Stock either with or without commission or other remuneration;
         or

14.3     entering into any contract of insurance with the Company or any
         subsidiary or any person so associated for a premium or other
         consideration; or

14.4     otherwise at any time contracting or entering into any contract or any
         financial or other transaction with the Company or any subsidiary or
         any person so associated or being Interested in any such contract or
         transaction; or

14.5     accepting or holding the trusteeship of any other Trust constituting or
         securing any other securities issued by the Company or any subsidiary
         or any person associated and neither it nor they shall not be liable to
         account whether to the Company or any subsidiary or any person so
         associated or the Stockholders, for any profit made or customary share
         of brokerage or commission received by it or them as a result.



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15.      LENDER CONSENTS

         Any consent granted by the Lender pursuant to this instrument may be
         granted on such terms and subject to such conditions (if any) as the
         Lender may in its absolute discretion determine and may be given
         retrospectively. Any breach of or failure to, comply with any of such
         terms and conditions by the Company shall constitute a breach of this
         instrument.

16.      WAIVER BY LENDER

         The Lender may, resolution of the Stockholders, and on such terms and
         subject to such conditions as it shall think fit:

16.1     authorise or waive any proposed breach or any breach by the Company of
         any of the terms of this Instrument or the conditions of the Loan Stock
         or any proposed breach or breach by any subsidiary of such terms,
         without prejudice to the rights of the Lender in respect of any
         subsequent breach of any such terms; and

16.2     determine that any event which constitutes (or which, with the giving
         of notice and/or lapse of time or any other matter would constitute) an
         event on the happening of which the Loan Stock shall have or may become
         Immediately due and repayable shall not be treated as such for the
         purposes of this Instrument or the conditions, without prejudice to the
         rights of the Lender in respect of any subsequent such event.

17.      APPOINTMENT AND RETIREMENT OF TRUSTEES

17.1     The statutory power to appoint new trustees of this Instrument shall be
         vested in the Company, but no trustee shall be appointed who shall not
         previously have been approved by a resolution of the Stockholders. A
         trust corporation may be appointed as sole trustee of this Instrument.
         Wherever there shall be more than two trustees of this Instrument a
         majority of such trustees may exercise all the functions, powers and
         duties by this Instrument vested in the Lender generally.



                                      -12-
<Page>

17.2     A trustee may retire at any time, on giving to the Company not less
         than three months' written notice, without assigning any reason and
         without being responsible for any costs occasioned by such retirement.
         The retirement or removal of any trustee who Is the only trustee of
         this Instrument, shall not become effective until a successor trustee
         (being a trust corporation) or trustees is appointed in accordance with
         this clause.

18.      LENDER MAY ASSUME COMPLIANCE BY THE COMPANY

18.1     Except as expressly provided in this Instrument, the Lender shall be
         and is authorised to assume without enquiry, in the absence of
         knowledge by, or an express notice to it to the contrary, that the
         Company is duly performing and observing all the terms of this
         Instrument and the conditions to be performed and observed by the
         Company.

         term, it shall be In the discretion of the Lender whether to take any
         action or proceedings or to enforce performance until in any such case
         the Lender are required to do so by a resolution of the Stockholders or
         in writing by not less than two fifths of the Stockholders and then
         only if the L ender shall be indemnified to its satisfaction against
         all actions, proceedings and claims to which it may render itself
         liable and all costs, charges, damages and expenses which it may Incur
         by so doing.

19.      MISCELLANEOUS

19.1     The headings to the clauses and conditions and any underlining in this
         Instrument and in the schedules are for ease of reference only and
         shall not form any part of this Instrument for the purposes of
         construction.

19.2     This Instrument and the appendices set out the entire terms and
         conditions in connection with the Loan Stock.

19.3     If at any time any term or provision in this Instrument including the
         appendices shall be hold to be illegal, invalid or unenforceable, In
         whole or in part, under any


                                      -13-
<Page>

         rule of law or enactment, such term or provision or part shall to that
         extent be deemed not to form part of this Instrument, but the
         enforceability of the remainder of this Instrument shall not be
         affected.

20.      GOVERNING LAW AND JURISDICTION

         This Instrument and the schedules shall be governed by and construed in
         accordance with English law and the Company, the Lender and the
         Stockholders hereby submit to the exclusive jurisdiction of the English
         courts.

                  IN WITNESS WHEREOF this Instrument has been executed by the
Company as a deed on the day and in the year first written above.

                               MEDICSIGHT LIMITED

                   (INCORPORATED UNDER THE COMPANIES ACT 1985)

                       CONVERTIBLE SECURED LOAN STOCK 2004
                               (THE "LOAN STOCK")

Principal amount of Loan Stock:                       No.:
(pound)[                ]                             [ ]



Issue of F-[ I ("the Principal Amount") Convertible Secured Loan Stock (part of
an issue of El 0,000,000 Convertible Secured Loan Stock 2004) created, pursuant
to the Memorandum and Articles of Association of the Company, by a resolution of
the board of directors of the Company passed on ( ] November 2001.

THIS IS TO CERTIFY THAT:

The [name] of [address] is the registered holder of E [ ] Loan Stock fully paid.
The holder of the Loan Stock is and will be entitled to the benefit of and will
be subject to the provisions contained in an instrument entered into by the
Company and dated [ ] November 2001 which include the terms and conditions
endorsed on this certificate.

Interest at the rate of 2 per cent, per annum above LIBOR is payable in
accordance with the provisions of condition 2.

DATED this        day of   2001



                                      -14-
<Page>

EXECUTED AS A DEED        )
AND DELIVERED on behalf of)
MEDICSIGHT by:            )...........................................Director

                           .................................Director/Secretary

NOTE: No transfer of this Loan Stock may be made without the production of the
certificate relating to it, which certificate must be surrendered before any
transfer can occur. The Loan Stock is transferable in multiples of F-1,000.



                                      -15-
<Page>




                                   CONDITIONS

1.1      The Company shall, unless It shall already have done so under the
         provisions of condition 7, pay the whole of the Principal Amount to
         the.Stockholder on [ ] November 2004

1.2      On making a payment under condition 1.1, the Company shall pay to the
         Stockholder interest accrued under condition 2 on the Principal Amount
         down to the date of payment

1.3      The Company may, if the balance of the Principal Amount outstanding
         after conversion has taken place pursuant to condition 3, is less than
         E1,000 pay the whole (but not part only) of the Principal Amount then
         outstanding to the Stockholder at any time

2.       The Company shall, on the day the Principal Amount is due to be repaid,
         pay interest on the Principal Amount to the Stockholder at the rate of
         2 per cent over the London Inter-Bank Offered Rate for Sterling of an
         amount equal to the Principal Amount (or if quotations cannot readily
         be obtained for such an amount, the average of the amounts for which
         quotations can be readily obtained higher and lower than the Principal
         Amount) at 11.00 am London time on the date of this Loan Stock for a
         period of one year (or if quotations for a period of one year are not
         available, for the longest period that is less than one year) and a
         certificate from Barclays Bank Pic (or any other bank selected by the
         Company) as to the rates offered to that bank shall be conclusive and
         binding on the Company and the Stockholder.

3.1      If, before the Principal Amount has been repaid by the Company to the
         Stockholder, the Company shall announce an Offer for Subscription,
         Placing or other public offering of Its ordinary shares, the
         Stockholder may give notice to the Company (and shall at the same time
         send this Deed to the Company) but no later than the earlier of (a) (I)
         the time allowed for applicants to apply for ordinary shares In an
         Offer for Subscription, or (11) fifteen days after ordinary shares in
         the Company are placed or (III) the date on which any other public
         offering closes (as the case may be) and (b) the due date for the
         repayment of the Principal Amount In accordance with condition 1.1,
         that it wishes to convert its rights In relation to the Principal
         Amount and interest thereon, or any part thereof, Into ordinary shares
         in the Company save that the Stockholder may only give notice to
         convert with the Company's written consent if the Stockholder has
         exercised any of its rights contained In condition 5. A notice given as
         provided by this condition 3 may not be withdrawn without the consent
         of the Company. The Company shall on the day an Offer for Subscription
         or other public offering (other than a Placing) closes or in any other
         case five business days after receipt of such notice, allot to the
         Stockholder ordinary shares in the Company at the same price per share
         as the shares are offered by the Company in the Offer for


                                      -16-
<Page>

         Subscription, Placing or other public offering.

3.2      The ordinary shares so allotted shall be credited as fully paid and
         shall rank parl passu in all respects at that time with the fully paid
         ordinary shares in the Company which are issued pursuant to the Offer
         for Subscription, Placing or other public offering

3.3      If any part of the Principal Amount shall remain outstanding after
         conversion, and shall not then be repaid pursuant to condition 1, the
         Company shall following conversion of that part of the Principal Amount
         converted into ordinary shares, issue to the Stockholder a Deed for the
         balance of the Principal Amount

3.4      Interest shall cease to be payable on the Principal Amount (or such
         part thereof as shall be converted Into ordinary shares of the Company)
         on the date the Company shall allot such shares to the Stockholder

4.1      The Company shall not, while It has outstanding any obligations under
         the Loan Stock, permit there to be in issue any equity share capital
         (as defined in Section 744 of the Companies Act 1985) In the Company
         which is not In all respects uniform with the ordinary shares in the
         Company which are in issue at the date hereof save:

         (a)      as to the date from which such capital shall rank for
                  dividend;

         (b)      by the Company in general meeting to staff and employees
                  (including directors holding executive office with the Company
                  or any of its subsidiaries); or

         (c)      for any share capital which has attached thereto rights as to
                  dividend, capital and voting which are in no respect more
                  favourable than those attached to the ordinary shares in the
                  Company in issue at the date such issue is publicly announced

4.2      The Company shall procure that during the period (if any) that the
         Stockholder may exercise any conversion rights, there are sufficient
         unissued ordinary shares in the authorised share capital of the Company
         to satisfy the rights of the Stockholder under condition 3

4.3      The Company shall not, while it has outstanding any obligations under
         the Loan Stock, issue any equity share capital that would result in the
         ordinary shares to be issued to the Stockholder upon conversion to be
         Issued at less than their nominal value

4.4      The Company shall send to the Stockholder (a) a copy of every document
         sent to the holders of ordinary shares at the same time as it is sent
         to the holders of ordinary shares and (b) a copy of every Offer for
         Subscription document, Placing memorandum or other Placing document,
         and any other document relating to a public offering of any shares in
         the Company on the day such document Is


                                      -17-
<Page>

         published or otherwise first made available to any prospective placee
         or other offeree of shares In the Company

4.5      After making payment under the provisions of condition 1 .1 or 1.2, as
         the case may require or allotting ordinary shares under the provisions
         of conditions 2.1, the Company shall have no further obligations by
         virtue of the provisions of this Deed

5.       The Principal Amount and interest thereon is secured by an instrument
         made on November 2001 between the Company (1) and Asia IT Capital
         Investments Limited for itself and as trustee for the Stockholders (2)
         by way of fixed and floating charges on all the Company's undertaking
         and assets, subject to a first charge in favour of HTTP Technology,
         Inc. dated 9 November 2001. The Company may not create charges ranking
         in priority to or pari passu with the charge in favour of the
         Stockholders.

6.       The Company shall not without the written consent of Stockholders
         holding not less than three quarters of the total of the Secured Loan
         Stock 2004 outstanding, or the consent of a special resolution of the
         Stockholders, while it has outstanding any obligations under this deed
         do any of the following:

6.1      Reduce the capital of the Company;

6.2      Cancel any part of the Company's share premium account;

6.3      Redeem any of the Company's shares;

6.4      Purchase any of the Company's shares; or

6.5      Permit any subsidiary of the Company to do any of the above

7.1      Notwithstanding the provisions of Condition 1 the Principal Amount
         together with all outstanding interest accrued thereon shall be payable
         immediately if: (i) the Company shall enter into any composition or
         arrangement with or for the benefit of its creditors; (ii) the Company
         shall become unable to pay Its debts as that expression is defined in
         Section 123 of the Insolvency Act 1986; (iii) any order shall be made,
         petition presented or resolution passed for the winding up of the
         Company save in connection with a scheme of arrangement for the
         reorganisation of the Company or for the amalgamation of its business
         and undertaking of that and any other company or companies;

         (i)      a petition shall be presented for the making of an
                  administration order, within the meaning of Section 8 of the
                  Insolvency Act 1986, in relation to the Company;

         (ii)     a receiver shall be appointed or a mortgagee shall enter into
                  possession of any of the assets of the Company or if any
                  mortgagee shall otherwise seek to enforce the security of any
                  such mortgage;

         (iii)    sell or attempt to sell any of the assets over which the
                  Company has created fixed charges as described In condition 3,
                  or deal with any of the assets over which the Company has
                  created a floating charge otherwise than In the ordinary
                  course of business;

         (iv)



                                      -18-
<Page>

         (v)      a petition shall be presented for the making of an
                  administration order, within the meaning of Section 8 of the
                  Insolvency Act 1986, in relation to the Company;

         (vi)     a receiver shall be appointed or a mortgagee shall enter into
                  possession of any of the assets of the Company or if any
                  mortgagee shall otherwise seek to enforce the security of any
                  such mortgage;

         (vii)    sell or attempt to sell any of the assets over which the
                  Company has created fixed charges as described In condition 3,
                  or deal with any of the assets over which the Company has
                  created a floating charge otherwise than In the ordinary
                  course of business;

         (viii)   the Company or any subsidiary shall breach any of the terms of
                  condition 6;

         (ix)     the Company shall stop payment or shall cease or threaten to
                  cease to carry on substantially the whole of Its business; or

         (x)      if default is made by the Company in performance of its
                  obligations under these conditions or under the terms of the
                  Loan Stock Instrument (other than any covenant for the payment
                  of principal and interest in respect of the Loan Stock) and
                  (except where, In the opinion of the Lender, such default Is
                  not capable of remedy when no such continuation or notice as
                  is referred to below will be required) such default continues
                  for more than 14 days after the Lender give the Company
                  written notice requiring such default to be remedied.

7.2      Any payment of the Principal Amount; made by virtue of the provisions
         of condition 7.1 shall be deemed for all purposes of this Deed to have
         been made under the provisions of condition 1.1

8.       Any change of address on the part of the Stockholder shall be notified
         to the Company Immediately

9.       The Company will recognise the Stockholder as the absolute owner of the
         Principal Amount and will not be bound to take notice of or to see to
         the execution of any trust whether express, Implied or constructive to
         which the Principal Amount may be subject and the receipt by the
         Stockholder of the Principal Amount, shall be a good discharge to the
         Company notwithstanding any notice that It may have whether express or
         otherwise of the right, title, interest or claim of any other person to
         or in the Principal Amount

10.1     The Stockholder will be entitled to transfer the Principal Amount (in
         multiples of E1,000) together with accrued Interest by a transfer in
         writing In the usual common form. There shall not be Included in any
         transfer any loan Stocks or other monies payable by the Company other
         than the Principal Amount together with accrued Interest. Such transfer
         must be signed by the transferor who shall



                                      -19-
<Page>

         be deemed to remain the owner of the Principal Amount together with
         accrued interest until the name of the transferee is entered In the
         register of Loan Stockholders. The transfer need not be a deed.

10.2     Each transfer of the Principal Amount together with accrued Interest
         must be left at the registered office for the time being accompanied by
         this Deed and such other evidence (if any) as the directors of the
         Company may require to prove the title of the transferor or his right
         to transfer the Principal Amount and accrued Interest, and if the
         transfer Is executed by some other person on his behalf, the authority
         of that person to do so. All transfers may be retained by the Company.
         No fee will be charged in respect of any transfer or for the
         registration of any probate, letters of administration, certificate of
         marriage or death, power of attorney or other document relating to or
         affecting the title of the Principal Amount and accrued interest. The
         ability to transfer may be suspended at such times and for such periods
         as the Company may determine save that such suspension shall not be
         more than 30 days in any one year. No transfer of the Principal Amount
         shall occur or be permitted where notice of repayment or conversion has
         been given.

         the death or bankruptcy of the Stockholder may (upon producing such
         evidence as the directors of the Company shall think sufficient that he
         sustains the character In respect of which he proposes to act under
         this condition or of his title) become the holder of the Principal
         Amount and accrued interest or (subject to the preceding conditions as
         to transfer) may transfer the Principal Amount and accrued interest.
         The Company may retain the Principal Amount which any person under
         condition -10 is entitled to transfer until such person shall become
         the holder or transfer the same as aforesaid

12       The principal monies or any other monies payable on or in respect of
         the Principal Amount and interest by the Company may be paid by cheque
         or warrant and sent through the post to the registered address of the
         Stockholder. Payment of the cheque or warrant by the bank on whom it is
         drawn shall be a satisfaction of the monies represented thereby. Every
         such cheque or warrant shall be sent at the risk of the person entitled
         to the Principal Amount and interest represented thereby.

13       If this Deed becomes worn out or defaced then upon production of such
         Deed to the directors of the Company, the Company may cancel It and may
         issue a new Deed in lieu of It and If any such Deed is lost or
         destroyed then upon proof of such loss or destruction to the
         satisfaction of the directors of the Company and upon such terms as to
         evidence an indemnity and the payment of out of pocket expenses of the
         Company In investigating evidence as the directors of the Company may
         deem adequate being given, a new Deed in lieu of that lost or destroyed
         may be given to the person(s) entitled to such lost or destroyed Deed.
         A record of the indemnlty (if any) shall be retained by the Company



                                      -20-
<Page>

14       A notice or document (including this Deed) may be served by the Company
         on the Stockholder either personally or by sending it by first class
         post in a pre-paid envelope addressed to such Stockholder at his
         registered address or, if he has no registered address within the
         United Kingdom, to the address (if any) within the United Kingdom
         supplied by him to the Company as his address for the service of
         notices, Where a notice or other document Is served by post, service
         shall be deemed to be effected on the second business day after the
         envelope containing the same is posted and in proving such service it
         shall be sufficient to prove that such envelope was properly addressed,
         stamped and posted. A notice may be served on the Company by sending it
         by first class post in a pre-paid envelope addressed to the Company at
         its registered office


EXECUTED AS A DEED          )
AND DELIVERED on behalf of  )
MEDICSIGHT LIMITED by:      )  /s/ S.ALLESCH-TAYLOR.....................Director

                               ........................................Secretary


EXECUTED AS A DEED          )
AND DELIVERED on behalf of  )
MEDICSIGHT LIMITED by:      )  /s/ W. PATERSON BROWN....................Director

                               ...............................Director/Secretary





                                      -21-