<PAGE>

                                                                   EXHIBIT 10.20

TRIO-TECH
---------


22 September 2000                               [SAMP]    BY HAND
                                                          -------
Marketing & Sales Department
Jurong Town Corporation
The JTC Summit
8 Jurong Town Hal Road
Singapore 609434

Attn: Mss Jenny Lim

ACCEPTANCE OF OFFER OF TENANCY FOR THE PREMISES AT BLK 1008 TOA PAYOH NORTH #07-
17 TO #07-18 TOA PAYOH INDUSTRIAL ESTATE SINGAPORE 318996

1.   We refer to your letter of offer dated 12 September 2000 for the Tenancy
     and hereby confirm our acceptance of all the covenants, terms and
     conditions stipulated therein.

2.   We enclose herewith a cheque for the amount of S$6,015.37 and the Banker's
     Guarantee as security deposit as confirmation of our acceptance.

3.   In addition, we also enclose herewith a duly completed GIRO authorization
     form.


                                 By: /s/ Yong Siew Wai

--------------------------------------------------------------------------------

Name of authorised signatory  :  Mr. Yong Siew Wai
Designation                   :  President/CEO
For and on behalf of

TRIO-TECH INTERNATIONAL PTE LTD

In the presence of
                                 By:/s/ Betty Ang

--------------------------------------------------------------------------------

Name of witness               :  Ms. Betty Ang
NRIC No.                      :  S6945849A
<PAGE>

JTC(L)3601/2506 Temp
                                        DID: 8833427
12 September 2000                       FAX: 8855899

                                        Email: chenwan@jtc.gov.sgv
TRIO-TECH INTERNATIONAL PTE LTD                                 J T C
Blk 1008 Toa Payoh North
#03-09/18
Singapore 318996
                                    BY LUM
                                    ------
(Attn: Mr Yong Siew Wai)

Dear Sirs,

OFFER OF TENANCY FOR FLATTED FACTORY SPACE

1 .  We are pleased to offer a tenancy of the Premises subject to the following
     covenants, terms and conditions in this letter and in the annexed
     Memorandum of Tenancy ("the Offer"):

     1.01 Location:

     Pte Lot A19597(d), Blk 1008 ("the Building") Toa Payoh North #07-17 to
     #07-18, Toa Payoh Industrial Estate Singapore 318996 ("the Premises") as
     delineated and edged in red on the plan attached to the Offer.

     1.02 Term of Tenancy:

          3 years ("the Term") with effect from 1 December 2000 ("the
          Commencement Date").

     1.03 Tenancy Agreement:

          Upon due acceptance of the Offer in accordance with clause 2 of this
          letter, you shall have entered into a tenancy agreement with US ("the
          Tenancy") and will be bound by the covenants, terms and conditions
          thereof.

          In the event of any inconsistency or conflict between any covenant,
          term or condition of this letter and the Memorandum of Tenancy, the
          relevant covenant, term or condition in this letter shall prevail.

     1.04 Area:

          Approximately 400.90 square metres (subject to survey).
<PAGE>

                                       2
                                                           Jurong Town
                                                           Corporation

     1.05  Rent and Service Charge:

           Rent:
           -----

           (a)      Discounted rate of Dollars $11.54 per square metre per month
                    for so long as the Tenant shall occupy by way of tenancy an
                    aggregate floor area of 1000 square metres in the Building
                    or in the various flatted factories belonging to the
                    Landlord, and

          (b)       Normal rate of Dollars $11.90 per square metre per month in
                    the event that the said aggregate floor area occupied is at
                    any time reduced to below 1000 square metre (when the
                    discount shall be totally withdrawn) with effect from the
                    date of reduction in the said aggregate floor,

                    ("Rent" ) to be paid without demand and in advance without
                    deduction on the 1st day of each month of the year (i.e. 1st
                    of January, February, March, etc.). The next payment shall
                    be made on 1 January 2001.

                    Service charge:
                    ---------------

                    $2.10 per square metre per month, ("Service Charge") as
                    charges for services rendered by us, payable without demand
                    on the same date and in the same manner as the Rent, subject
                    to our revision from time to time.

     1.06  Security Deposit/Banker's Guarantee:

           You will at the time of acceptance of the Offer be required to place
           with us a deposit of Dollars $16,404.83 equivalent to 3 months' Rent
           (at the discounted rate) and Service Charge ("Security Deposit") as
           security against any breach of the covenants, terms and conditions in
           the Tenancy.

           The Security Deposit may be in the form of cash and/or acceptable
           Banker's Guarantee in the form attached (effective from 1 October
           2000 to 31 May 2004 ) and/or such other form of security as we may in
           our absolute discretion permit or accept.

           The Security Deposit must be maintained at the same sum throughout
           the Term and shall be repayable to you without interest or returned
           to you for cancellation, after the termination of the Term (by expiry
           or otherwise) or expiry of the Banker's Guarantee, as the case may
           be, subject to appropriate deductions or payment to us for damages or
           other sums due under the Tenancy.
<PAGE>

          If the Rent at the discounted rate is increased to the normal rate or
          Service Charge is increased or any deductions are made from the
          Security Deposit, you are to immediately pay the amount of such
          increase or make good the deductions so that the Security Deposit
          shall at all times be equal to 3 months' Rent and Service Charge.

1.07      Mode of Payment:

          Except for the payment to be made with your letter of acceptance
          pursuant to clause 2 of this letter, during the Term, you shall pay
          Rent, Service Charge and GST by Interbank GIRO or any other mode to be
          determined by us.

          [Note:Accordingly, you are to provide us with the duly completed GIRO
          -----
          authorization form enclosed herewith.

          # However, pending finalisation for the GIRO arrangement, you shall
          pay Rent, Service Charge and GST as they fall due by cheque.]

1.08      Permitted Use:

(a)         Subject to clause 1.12 of this letter, you shall commence full
            operations within four (4) months of the Commencement Date for the
            purpose of IC testing only and for no other purpose whatsoever ("the
            Authorised Use").

(b)         Thereafter, you shall maintain full and continuous operations and
            use and occupy the whole of the Premises for the Authorised Use.

(c)         Subject to clauses (a) and (b) above, you shall use and occupy at
            least sixty percent (60%) of the gross floor area of the Premises
            for industrial activities and ancillary stores, and use and occupy
            the remaining gross floor area, if any, for offices, neutral areas,
            communal facilities and such other uses as may be approved in
            writing by us and the relevant governmental and statutory
            authorities PROVIDED THAT you shall not use and occupy the Premises
            for the purpose of commercial office and storage unrelated to the
            Authorised Use.

1.09      Approvals

The Tenancy is subject to approvals being obtained from the relevant government
and statutory authorities.
<PAGE>

                                       4
                                                         Jurong Town Corporation

1.10 Possession of Premises:

(a)       Keys to the Premises will be given to you two (2) months prior to the
          Commencement Date subject to due acceptance of the Offer ("Possession
          Date").

(b)       From the Possession Date until the Commencement Date, you shall be
          deemed a licensee upon the same terms and conditions in the Tenancy.

(c)       if you proceed with the Tenancy after the Commencement Date, the
          licence fee payable from the Possession Date to the Commencement Date
          shall be waived ("Rent-Free Period"). Should you fail to so proceed,
          you shall:

               (i)    remove everything installed by you;
               (ii)   reinstate the Premises to its original state and
                      condition; and
               (iii)  pay us a sum equal to the prevailing market rent payable
                      for the period from the Possession Date up to the date the
                      installations are removed and reinstatement completed to
                      our satisfaction,

     without prejudice to any other rights and remedies we may have against you
     under the enancy or at law.

1.11 Preparation and Submission of Plans:

(a)       No alteration, addition, improvement, erection, installation or
          interference to or in the Premises or the fixtures and fittings
          therein is permitted without Building Control Unit [BCU(JTC)] prior
          written consent. Your attention is drawn to clauses 2.10 to 2.19 and
          2.34 of the Memorandum of Tenancy.

(b)       You will be required to prepare and submit floor layout plans of your
          factory and plans of the air-conditioning works in accordance with the
          terms of the tenancy and the 'Guide' attached. It is important that
          you should proceed with the preparation and submission of the plans in
          accordance with the procedures set out in the said 'Guide'.

(c)       Should there be alteration of existing automatic fire alarm and
          sprinkler system installation, alteration plans shall be submitted to
          Building Control Unit [BCU(JTC)] for approval on fire safety aspects.
          All air-conditioning, fire alarm & sprinkler system plans must be
          signed by a relevant Professional Engineer, registered with the
          Professional Engineers Board of Singapore.


<PAGE>

                                       5
                                                         Jurong Town Corporation

(d)     Upon due acceptance of the Offer, a copy of the floor and elevation
        plans (transparencies) will be issued to you to assist in the
        preparation of the plans required herein.

(e)     No work shall commence until the plans have been approved by Building
        Control Unit [BCU(JTC)].

1.12 Final inspection:

You shall ensure that final inspection by us of all installations is carried
out and our approval of the same is obtained before any operations in the
Premises may be commenced.

1.13  Special Conditions:

(1)            Normal (Ground & Non-ground) Floor Premises
               -------------------------------------------

        You shall comply and ensure compliance with the following restrictions:

        (a)    maximum loading capacity of the goods lifts in the Building; and

        (b)    maximum floor loading capacity of 10.00 kiloNewtons per square
               metre of the Premises on the 7th storey of the Building PROVIDED
               THAT any such permitted load shall be evenly distributed.

        We shall not be liable for any loss or damage that you may suffer from
        any subsidence or cracking of the ground floor slabs and aprons of the
        Building.

(2)  Option for renewal of tenancy
     -----------------------------

        (a)    You may within 3 months before the expiry of the Term make a
               written request to us for a further term of tenancy.

        (b)    We may grant you a further term of tenancy of the Premises upon
               mutual terms to be agreed between you and us subject to the
               following:

               (i)   there shall be no breach of your obligations at the time
                     you make your request for a further term;

               (ii)  our determination of revised rent, having regard to the
                     market rent of the Premises at the time of granting the
                     further term, shall be final;
<PAGE>

                              6
                                                         Jurong Town Corporation

               (iii)  we shall have absolute discretion to determine such
                      covenants, terms and conditions, but excluding a covenant
                      for renewal of tenancy; and

               (iv)   there shall not be any breach of your obligations at the
                      expiry of the Term.

2.   Mode of Acceptance:

          The Offer shall lapse if we do not receive the following by 26
          September 2000:-

          .    Duly signed letter of acceptance (in duplicate) of all the
               covenants, terms and conditions in the Tenancy in the form
               enclosed at the Appendix.
               (Please date as required in the Appendix)

          .    Payment of the sum set out in clause 4.

          .    Duly completed GIRO authorization form.

3.   Please note that payments made prior to your giving us the other items
     listed above may be cleared by and credited by us upon receipt. However, if
     the said other items are not forthcoming from you within the time
     stipulated herein, the Offer shall lapse and there shall be no contract
     between you and us arising hereunder. Any payments received shall then be
     refunded to you without interest and you shall have no claim of whatsoever
     nature against us.
<PAGE>

                                       7

                                                         Jurong Town Corporation

4.          The total amount payable is as follows:

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------------------------
                                                  Amount                                  +3 % GST
--------------------------------------------------------------------------------------------------
<S>                                               <C>                   <C>               <C>
Rent at $11.54 psm per month on
400.90 sq m for the period 1 December
2000 to 31 December 2000                             $4,626.39
--------------------------------------------------------------------------------------------------
Less:
--------------------------------------------------------------------------------------------------
3% property tax rebate on rental value               $  138.79
                                                     ---------
                                                     $4,487.60
--------------------------------------------------------------------------------------------------
Service Charge at $2.10 psm per
month on400.90sq m for the period
1 December 2000 to 31 December 2000                  $  841.89          $ 5,329.49        $159.88
                                                     ---------
--------------------------------------------------------------------------------------------------
Deposit equivalent to three months'
rent and service charge (or Banker's
Guarantee provided in accordance with
sub-paragraph 1.06 above)                                               $16,404.83
--------------------------------------------------------------------------------------------------
Stamp fee payable on Letter of
Acceptance which will be stamped by
JTC on your behalf                                                      $   526.00
--------------------------------------------------------------------------------------------------
Sub-Total Payable                                                       $22,260.32        $159.88
--------------------------------------------------------------------------------------------------
Add: GST + 3%                                                           $   159.88
                                                                        ----------
--------------------------------------------------------------------------------------------------
Total Amount Payable                                                    $22,420.20
                                                                        ==========
--------------------------------------------------------------------------------------------------
</TABLE>

5.   Rent-Free Period:


     As the Commencement Date will not be deferred, we advise you to accept the
     Offer as soon as possible and to collect the keys to the Premises on the
     scheduled date in order to maximize the Rent-Free Period referred to in
     clause 1.10(c) of this letter.

6.   Variation to the Tenancy

     This letter and the Memorandum of Tenancy constitute the full terms and
     conditions governing the Offer and no terms or representation or otherwise,
     whether express or implied, shall form part of the Offer other than what is
     contained herein, Any variation, modification, amendment, deletion,
     addition or otherwise of the covenants, terms and conditions of the Offer
     shall not be enforceable unless agreed by both parties and reduced in
     writing by us.
<PAGE>

                                       8
                                                         Jurong Town Corporation

7.   Car-Parking Scheme:

     (a)  The car park for Blk 1008 Toa Payoh North is currently managed by a
          Tenants' Committee and you will:

          (i)    have to contribute towards all the operational and management
                 costs, if any, incurred in connection with the car parks;

          (ii)   observe and be bound by all the rules and regulations governing
                 the use and operation of the car park. A copy of the Tenant
                 Committee's current rules and regulations is obtainable from
                                                           ------------------
                 the Tenants' Committee. You are required to contact:
                 ---

                 Miss Susan Ng
                 Wilson Parking (S) Pte Ltd
                 32 Sultan Centre
                 Singapore 198480
                 TelNo:2966600

                 a member of the Committee, on your use of the car park.

     (b)  The Corporation shall not be liable for any loss, damage,
          injury, liabilities, claim or action you may sustain or
          suffer in the use of the car park and the tenants shall
          fully indemnify the Corporation against any loss, claims,
          penalties, demands, damage arising from the private
          management and operations of the car park by the tenants.

8.   Application for Approvals, Utilities etc.

     Upon your acceptance of the covenants, terms and conditions of the Offer,
     you are advised to proceed expeditiously as follows:

     8.01 Preliminary Clearance:

          Comply with the requirements of the Chief Engineer (Central Building
          Plan Unit), Pollution Control Department and/or other departments
          pursuant to your application/s for preliminary clearance. (Please note
          that we have referred your application to the relevant department/s)

     8.02 Discharge of Trade Effluence:

          Complete the attached Application for Permission to Discharge Trade
          Effluent into Public Sewer and return the application form direct to
          the Head, Pollution Control Department, Ministry of Environment,
          Environment Building, 40 Scotts Road. Singapore 228231 (Telephone No.
          7327733).
<PAGE>

                                       9

                                                   Jurong Town Corporation

     8.03 Electricity:

          Engage a registered electrical consultant or competent contractor to
          submit three sets of electrical single-line diagrams to and in
          accordance with the requirements of our Property Support Department
          (PSD), Customer Services Group, JTC East Zone Office for endorsement
          before an application is made to the Power Supply Pte Ltd to open an
          account for electricity connection. Please contact our Property
          Support Department (PSD) at Blk 25 Kallang Avenue #05-01 Kallang Basin
          Industrial Estate Singapore 339416 direct for their requirements.

     8.04 Water:

          Submit four copies of sketch plans, prepared by a licensed plumber,
          showing the section and layout of the plumbing, to our Building
          Control Unit [BCU(JTC)] for approval prior to the issue of a letter to
          Water Conservation Department, Public Utilities Board to assist you in
          your application for a water sub-meter.

     8.05 Telephone:

          Apply direct to Singapore Telecommunications Ltd for all connections.

     8.06 Automatic Fire Alarm System ( Incorporating Heat Detector)

          Engage a registered electrical consultant/professional engineer to
          submit two sets of fire alarm drawings, indicating the existing
          fixtures if any, the proposed modifications of the fire alarm and the
          layout of machinery, etc to and in accordance with the requirements of
          our Building Control Unit [BCU(JTC)]. Please contact our Building
          Control Unit [BCU(JTC)] at The JTC Summit, Customer Service Centre
          (1st level) 8 Jurong Town Hall Road Singapore 609434 direct for
          further requirements.
<PAGE>

                                      10

                                                   Jurong Town Corporation

     8.07 Factory Inspectorate

          Complete and return direct to Chief Inspector of Factories the
          attached form, "Particulars to be submitted by occupiers or Intending
          Occupiers of Factories".

Yours faithfully

By:/s/ Jenny Lim

JENNY LIM (Ms)
MARKETING & SALES DEPARTMENT
INDUSTRIAL PARKS DEVELOPMENT GROUP
JURONG TOWN CORPORATION

Encl