<PAGE>
 
                                                                    EXHIBIT 10.8

                                                MASTER AGREEMENT NO. P/PS-960163
                                                                              





                                MASTER AGREEMENT

                                      FOR

                            THE PURCHASE OF PRODUCTS

                                      AND

         INVENTORY MAINTENANCE, ASSEMBLY AND FULFILLMENT (IAF) SERVICES

                                    BETWEEN

                          PACIFIC BELL MOBILE SERVICES

                                      AND

                                 CELLSTAR, LTD.


                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement







THIS AGREEMENT HAS CONFIDENTIAL PORTIONS OMITTED, WHICH PORTIONS HAVE BEEN FILED
SEPARATELY WITH THE SECURITIES AND EXCHANGE COMMISSION. OMITTED PORTIONS ARE
INDICATED IN THIS AGREEMENT BY "[REDACTED]".

<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

                               TABLE OF CONTENTS
                               -----------------
 
1. DEFINITIONS                                                            1
2. TERM OF AGREEMENT                                                      3
3. MASTER AGREEMENT                                                       3
4. SCOPE OF WORK                                                          4
   4.1 CUSTOMER PARTNER TEAM                                              4
   4.2 EXTERNAL RELATIONSHIPS                                             4
       4.2.1 Sourcing                                                     4
       4.2.2 Vendors and Product Suppliers                                5
       4.2.3 Retailers and Other Resellers                                6
       4.2.4 Direct Sales Accounts (Subscriber and Business Customers)    6
   4.3 WORKING RELATIONSHIP                                               6
       4.3.1 Dedicated Product Inventory Ownership and Management         6
       4.3.2 Open Stock Forecast and Supply                               7
       4.3.3 Product Assembly                                             7
       4.3.4 Credit Line Administration, Order Processing and Fulfillment 7
       4.3.5 Accounts Receivable, Invoicing and Collections               8
       4.3.6 Inventory Accounting and Control                             9
       4.3.7 Maintenance of Books and Records                             9
       4.3.8 Inventory/Warehousing                                        9
       4.3.9 Returns Processing                                           9
       4.3.10 Use of Fictitious Business Name                             9
   4.4 COMPENSATION                                                      10
       4.4.1 Start-up Costs                                              10
       4.4.2 Inventory Carrying Costs                                    10
       4.4.3 Standard Product Cost                                       10
       4.4.4 Credit for Customer Receivable                              11
       4.4.5 Fulfillment Services Costs                                  11
       4.4.6 Monthly Recurring Service Fees                              11
       4.4.7 Returns                                                     11
       4.4.8 Purchase Price Variances                                    11
   4.5 PBMS/SUPPLIER AGREEMENTS                                          12
5. ORDERS                                                                13
6. PRICES                                                                14

                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

7. INVOICING AND PAYMENT                                                 14
8. SHIPPING AND PACKING                                                  15
9. TAXES                                                                 15
10. RECORDS AND AUDITS                                                   16
11. INDEPENDENT CONTRACTOR                                               16
12. NONEXCLUSIVE AGREEMENT                                               16
13. INDEMNIFICATION                                                      16
14. INSURANCE                                                            17
15. ACCESS                                                               18
16. INFORMATION                                                          19
17. QUALITY                                                              20
18. REGISTRATION                                                         21
19. INSIGNIA                                                             22
20. HAZARDOUS MATERIALS                                                  22
21. CODES, LAWS OR REGULATIONS                                           22
22. NOTICE OF DELAYS                                                     22
23. CHANGES AND SUSPENSIONS                                              22
24. TERMINATION AND CANCELLATION                                         23
25. PARTIAL TERMINATION OR CANCELLATION                                  23

                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

26. NONASSIGNMENT                                                        24
27. NOTICES                                                              24
28. PUBLICITY                                                            24
29. COMPLIANCE WITH LAWS                                                 24
30. TITLE                                                                25
31. NO THIRD PARTY BENEFICIARIES                                         25
32. AMENDMENTS AND WAIVERS                                               25
33. EXECUTIVE ORDERS                                                     25
34. HEADINGS                                                             25
35. GOVERNING LAW                                                        25
36. REMEDIES CUMULATIVE                                                  25
37. SEVERABILITY                                                         25
38. SURVIVAL                                                             26
39. PATENTS                                                              26
40. FORCE MAJEURE                                                        26
41. SUBCONTRACTING PLAN                                                  26
42. MBE/WBE/DVBE CANCELLATION CLAUSE                                     26
43. DELIVERY OF PRODUCTS AND PERFORMANCE OF SERVICES                     27
44. USE OF CELLSTAR'S PUBLISHED SPECIFICATIONS                           28

                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

45. DOCUMENTATION                                                        28
46. RISK OF LOSS                                                         28
47. WARRANTIES                                                           28
48. TERMINATION OF ORDERS                                                29
49. ALTERNATE DISPUTE RESOLUTION                                         29
50. PRECEDENCE                                                           30
51. LIMITATION OF LIABILITY                                              30
52. CORPORATE AUTHORIZATION                                              30
53. ENTIRE AGREEMENT                                                     31

                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

                                    EXHIBITS
                                    --------

EXHIBIT A:   Executive Orders and Associated Regulations

EXHIBIT A-1: Job Specific Subcontracting Plan

EXHIBIT A-2: MBE/WBE/DVBE Summary Subcontracting Report
             (Job Specific Results)

EXHIBIT A-3: Commodity Product Subcontracting Plan

EXHIBIT A-4: MBE/WBE/DVBE Summary Subcontracting Report
             (Commodity Results)

EXHIBIT B:   Description of Products, Services & Prices

EXHIBIT C:   PBMS' Credit and Collection Costs

EXHIBIT D:   PCS Price List

EXHIBIT E:   Sample Order

EXHIBIT F:   Assembly Cost Model

APPENDIX 1:  Procedures Manual

                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163
                                                                              

THIS MASTER AGREEMENT ("AGREEMENT"), EFFECTIVE SEPTEMBER 20, 1996, IS BETWEEN
CELLSTAR, LTD., A TEXAS LIMITED PARTNERSHIP ("CELLSTAR"), AND PACIFIC BELL
MOBILE SERVICES, A CALIFORNIA CORPORATION ("PBMS").  THE PARTIES, INTENDING TO
BE LEGALLY BOUND, AGREE AS FOLLOWS:

1.   DEFINITIONS

     For purposes of this Agreement, the following terms and all other terms
     defined in this Agreement shall have the meanings so defined unless the
     context clearly indicates otherwise.  A term defined in the singular shall
     include the plural and vice versa when the context so indicates.

     "AFFILIATE" - means with respect to PBMS (a) any corporation or other
     entity owning, either directly or indirectly, a majority of the outstanding
     stock of PBMS ("Parent"), or (b) any corporation or other entity in which a
     majority of the ownership interest is held, either directly or indirectly,
     by Parent or PBMS.

     "CELLSTAR ORDER" - means an order executed by CellStar under a product
     supplier/PBMS agreement.

     "COMPONENT INVENTORY" - means items carried in inventory at the component
     level for resale to subscribers as repair or replacement items.  These
     components are usually but not always "B Stock" items which have been
     received as returns without apparent defect or reconditioned merchandise
     which cannot be sold as new equipment.

     "CUSTOMERS" - means either Retailers, resellers, business and/or end users.

     "DEDICATED PRODUCTS" - means Products purchased by CellStar at PBMS"
     direction under terms negotiated by PBMS with the Product manufacturers.
     Subject to Section 4.3.1.c, Dedicated Products shall be reserved
     exclusively for PBMS' use.

     "FULFILLMENT SERVICES" - means picking, assembling of Products, packaging,
     preparation of shipping documents, shipping to Customers, processing of
     Customer returns and tracking of shipments and all associated Services
     associated with providing Products to Customers and receiving Products back
     from Customers.

     "INFORMATION" - means all ideas, discoveries, concepts, know-how,
     techniques, designs, specifications, drawings, sketches, models, manuals,
     samples, tools, pricing, Customer lists, competitor, manufacturer, or
     manufacturing information, computer programs, technical information, and
     other confidential business, Customer or personnel information or data,
     whether written, oral or otherwise owned or controlled by the disclosing
     party.

     "INSIGNIA" - means PBMS' and as applicable, the manufacturers' trademarks,
     trade names, symbols, decorative designs or evidence of PBMS' inspection.

                                       1
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                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

     "MATERIAL ADVERSE CHANGE" - means a material adverse change in (a) the
     business assets, operations, prospects or financial condition of either
     party, or (b) the ability of either party to perform its obligations under
     this Agreement.

     "OPEN STOCK" - means Products  purchased  at CellStar's discretion and in
     CellStar's inventory available to the general market.

     "OPEN STOCK INVENTORY" - means original equipment manufacturer accessories
     carried in inventory by CellStar for sale to PBMS and other CellStar
     customers.  These items may be packaged as PBMS branded items in unique
     PBMS retail packages.  When so packaged at the request of PBMS, these items
     are converted to "Dedicated Products".

     "ORDERS" - means purchase orders, in written (e.g. mailed or faxed), or
     electronic form (e.g. EDI, flat file) as may be delivered to CellStar for
     the purpose of ordering Products and/or Services hereunder. A purchase
     order shall be substantially in the form of Exhibit E (Sample Order)
     attached hereto and made a part hereof.  Each such purchase order, in
     written or electronic form shall be deemed to be a separate and independent
     agreement between the parties thereto with respect to the subject matter
     thereof and shall incorporate (a) all of the provisions of this Agreement
     (including any appendices, exhibits, specifications and other documents
     attached hereto) as it may from time to time be amended, and (b) any
     specifications attached thereto.

     "PCS" - means Personal Communication Services.

     "PROCEDURES MANUAL" - means a multi-paged document, (the initial version of
     which is attached hereto and incorporated by reference hereto as Appendix
     1), which details processes and deliverables which will be routinely
     performed in the relationship between CellStar and PBMS, and which shall be
     periodically revised, from time to time, upon written agreement by both
     parties.

     "PRODUCTS" - means the equipment and materials, including but not limited
     to: PCS handsets, accessories, and collateral material, as may be furnished
     to PBMS' Customers by CellStar hereunder.

     "PURCHASE PRICE VARIANCE" - means the difference between the actual
     delivered cost of Products or components and the standard cost contained in
     CellStar's accounting systems.

     "RETAILER" - means any vendor of products, whether through traditional
     retail outlet or through membership or discount or wholesale establishments
     selling to the end user consumer.

     "SERVICES" - means all services furnished by CellStar hereunder to PBMS
     and/or to PBMS' Customers.

     "SPECIFICATIONS" - means CellStar's commercial and technical specifications
     (including drawings) for the Products and Services provided hereunder and
     such other specifications, e.g. (Procedures Manual), as are listed in the
     exhibits or appendices, attached hereto  and made a part hereof, or as are
     attached to and made a part of the applicable Order.

                                       2
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

     "WARRANTY" - means the warranties for CellStar's Services or the Products
     covered by CellStar's and/or the Product manufacturer's warranties under
     this Agreement.

2.   TERM OF AGREEMENT
     a. This Agreement shall become effective as of the date stated above (the
        "Effective Date"), and unless sooner terminated or canceled as provided
        herein, shall continue through September 20, 2001.
     b. Either CellStar or PBMS may terminate this Agreement upon one hundred
        and eighty (180) calendar days' prior written notice to the other
        setting forth the effective date of such termination. The termination,
        cancellation or expiration of this Agreement shall not affect the
        obligations of the parties under any Order previously executed
        hereunder, and the terms and conditions of this Agreement shall continue
        to apply to such Order as if this Agreement had not expired, or been
        terminated or canceled.  Upon the termination, cancellation or
        expiration of this Agreement, PBMS agrees to purchase any Dedicated
        Products remaining in CellStar's inventory, including any Open Stock
        inventory which has been converted to Dedicated Product inventory.

3.   MASTER AGREEMENT

     a  This Agreement anticipates the future issuance of Orders by Pacific Bell
        Mobile Services and any PBMS Affiliate as may be designated by Pacific
        Bell Mobile Services in writing.  Each such entity executing an Order
        shall be deemed to be a party to that Order and shall be subject to the
        terms and conditions of this Agreement for purposes of that Order;
        provided that no PBMS Affiliate shall be permitted to issue an Order
        hereunder until (i) such Affiliate has satisfied CellStar's credit
        standards, and (ii) an authorized representative of such Affiliate has
        executed appropriate documentation pursuant to which it agrees to be
        bound by the terms and conditions of this Agreement for the obligations
        incurred under such Order.  For the purposes of any Order executed
        hereunder by any PBMS Affiliate, the term "PBMS" in this Agreement shall
        be deemed to also refer to such Affiliate where the context so
        indicates.  Prior to any Affiliate's execution of an Order hereunder,
        PBMS shall obtain that Affiliate's written agreement to be bound by all
        the terms and conditions of this Agreement.

     b. The provisions of this Agreement shall apply to all contracts entered
        into between CellStar and PBMS during the term of this Agreement with
        respect to the Products and Services which are the subject of this
        Agreement unless the parties expressly agree otherwise by a written
        modification to this Agreement, signed by the persons who executed this
        Agreement or any other authorized representative of the parties, or
        unless an Affiliate of PBMS enters into a separate written agreement
        with CellStar, signed by CellStar and the persons authorized to execute
        agreements for the PBMS Affiliate.  Any such separate agreement signed
        between CellStar and a PBMS Affiliate shall apply only to CellStar and
        such Affiliate and have no effect 

                                       3
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

        whatsoever on PBMS. In the absence of such a modification to this
        Agreement or such separate agreement, any terms in any other contract
        respecting the subject matter of this Agreement which are additional to,
        different from or inconsistent with the provisions of this Agreement
        shall be deemed to be void and of no effect whatsoever.

4.   SCOPE OF WORK

     This Agreement describes the principles of the relationship between PBMS
     and CellStar and describes CellStar's provision of Products and value added
     Services, including but not limited to, sourcing, inventory, assembly,
     credit, collections and fulfillment Services to support Product
     distribution to PBMS' Customers.

     4.1  CUSTOMER PARTNER TEAM
          The parties will jointly commit resources to support the following
          business processes and structures to accomplish PBMS' and CellStar's
          objectives under this Agreement.

          The Customer Partner Team ("CPT") shall set direction, priorities,
          expectations and boundaries and act to resolve business issues which
          arise. The CPT will particularly focus on emphasizing collaborative
          work between the parties and to preserve and promote partnering
          between the parties.

          CPT members shall consist of three (3) representatives each from
          CellStar and PBMS.  At least one representative from each party will
          be at the vice president level or higher.  Those representatives,
          together with the other CPT members shall be responsible for:

          1.   Maintaining and reviewing the Services cost structure;
          2.   Reviewing current processes and additional issues as the parties
               may identify for process improvements;
          3.   At least once each calendar quarter, reviewing pricing, and
               recommending price adjustments to the CPT, if necessary;
          4.   Reviewing forecasting, supply management, and delivery processes
               in an effort to streamline processes and to reduce costs
               associated with these processes for the benefit of both parties;
               and
          5.   Facilitating the Alternate Dispute Resolution ("ADR") process as
               defined in this Agreement.

     4.2  EXTERNAL RELATIONSHIPS

          4.2.1  SOURCING

               PCS Equipment.  PBMS has entered into, or may enter into,
               -------------                                            
               agreements ("PBMS/supplier agreements") with certain
               manufacturers or suppliers (hereinafter individually and
               collectively "product suppliers") for the purchase of Products.
               CellStar agrees that, except with respect to Open Stock, it
               shall, upon receipt of an Order by PBMS, place a CellStar 

                                       4
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

               Order under the PBMS/supplier agreement specified by PBMS for the
               quantity of Dedicated Products identified by PBMS in such Order.
               Notwithstanding the above, CellStar shall not be obligated to
               purchase Products on behalf of PBMS which will bring anticipated
               inventory above a level of expected 60 day sales. PBMS shall
               provide CellStar the applicable PBMS/supplier agreement (or all
               pertinent portions thereof) in order for CellStar to place a
               CellStar Order. If CellStar cannot abide by any term(s) set out
               in the PBMS/supplier agreement (or portions thereof) provided by
               PBMS, CellStar shall immediately notify PBMS and shall not
               proceed with placing a CellStar Order under such agreement until
               PBMS and CellStar expressly agree otherwise in writing. Further
               terms around CellStar's use of PBMS/supplier agreements are set
               forth in Section 4.2.2 below and the section entitled
               "PBMS/Supplier Agreements" of this Agreement.

          4.2.2  VENDORS AND PRODUCT SUPPLIERS
               a.   Generally, in this Agreement where the term "vendor" or
                    "manufacturer" is used, it means the supplier providing Open
                    Stock to CellStar.  Where the term "product supplier" is
                    used, it means the supplier providing Dedicated Products to
                    CellStar under a CellStar Order issued pursuant to the
                    PBMS/supplier agreement.
               b.   With respect to Dedicated Products, PBMS will be responsible
                    for product supplier selection and certification, product
                    selection, pricing and contract negotiations for Dedicated
                    Products.  As to each CellStar Order for Dedicated Products,
                    PBMS shall pass through to CellStar the rights of PBMS under
                    the product supplier agreement, including but not limited
                    to, product supplier indemnity and warranties applicable to
                    CellStar's use of the Dedicated Products, to the extent
                    allowed by the product supplier.  Nothing in this Agreement
                    shall diminish any pass-through warranties, indemnity or
                    other rights extended to CellStar through PBMS, by the
                    product suppliers.
               c.   If PBMS directs CellStar to issue a CellStar Order for the
                    purchase of Dedicated Products under a PBMS/supplier
                    agreement, PBMS will ensure that the product supplier has
                    granted CellStar all necessary rights to place that Order.
               d.   CellStar will procure, receive, inventory, pack for
                    shipping, ship, and disburse Dedicated Products received
                    from the vendors and product suppliers.
               e.   CellStar will be solely responsible for entering into any
                    necessary vendor agreements for the purchase of Open Stock
                    Products.  CellStar shall pass through to PBMS the rights of
                    CellStar under the vendor agreement, including but not
                    limited to, vendor indemnity and warranties applicable to
                    PBMS' and its Customers' use of the Open Stock Products, to
                    the extent allowed by the vendor.  Nothing in this Agreement
                    shall diminish any 

                                       5
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

                    pass-through warranties, indemnity or other rights extended
                    to PBMS through CellStar, by the vendor.

          4.2.3  RETAILERS AND OTHER RESELLERS
               a.   Generally all Customer contact will be through PBMS.
               b.   Generally, issues related to Customer payment, credit and
                    collections will be handled through CellStar.
               c.   CellStar will provide Products to Customers as specified in
                    Exhibit D and invoice Customers at PBMS' direction as stated
                    in the applicable Order or if not stated in the Order, as
                    specified in the Procedures Manual.
               d.   CellStar will process Customer returns in accordance with
                    PBMS' sales policy as specified in the Procedures Manual.

          4.2.4  DIRECT SALES ACCOUNTS (SUBSCRIBER AND BUSINESS CUSTOMERS)

               PBMS will handle all billing and accounts receivable transactions
               with direct sales account Customers. CellStar's primary
               responsibility in connection with Direct Sales Accounts ("Direct
               Sales Accounts") will be to provide fulfillment Services and to
               process Customer returns in accordance with the Procedures
               Manual.

     4.3  WORKING RELATIONSHIP
          The following processes will be contained and further described in the
          Procedures Manual:

          4.3.1  DEDICATED PRODUCT INVENTORY OWNERSHIP AND MANAGEMENT
               a.   CellStar will maintain inventories in its facilities and
                    will be responsible for risk of physical loss or damage, and
                    any requested insurance as is consistent with prepaid and
                    add conventions.
               b.   CellStar will determine inventory and safety stock levels
                    necessary to support PBMS' business pursuant to a rolling 90
                    calendar day forecast which PBMS shall provide and update
                    monthly.
               c.   PBMS and CellStar recognize that product suppliers may
                    prohibit sale of handsets outside PBMS' services territory.
                    In light of that recognition, PBMS and CellStar shall work
                    cooperatively with the product suppliers to dispose of slow-
                    moving stock.  If CellStar wishes to sell Dedicated Products
                    to third parties in addition to PBMS' Customers, CellStar
                    shall 1) gain the written consent of PBMS Director of
                    Procurement prior to the sale, and 2) if requested by PBMS
                    and at a charge to be agreed upon, remove the Insignia from
                    the Product.
               d.   CellStar will provide space for PBMS to perform quality
                    control inspections on inbound Dedicated Products as
                    reasonably required by PBMS, as specified in the Procedures
                    Manual.

                                       6
                         PROPRIETARY AND CONFIDENTIAL
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                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

          4.3.2  OPEN STOCK FORECAST AND SUPPLY
               a.   PBMS will provide a forecast of PBMS' requirements for Open
                    Stock Products on a rolling 90 calendar day forecast.  Such
                    forecast shall be updated by PBMS.
               b.   CellStar will advise PBMS promptly, within 2 business days,
                    of any Open Stock vendor supply constraints.
               c.   CellStar will make reasonable best efforts to provide Open
                    Stock Product availability to fill all PBMS Orders.

          4.3.3  PRODUCT ASSEMBLY
               a.   CellStar will assemble and package components to PBMS'
                    specifications.
               b.   CellStar will control the security and data collection
                    processes for SIM cards.
               c.   CellStar will provide PBMS with sales forecasting and
                    DRP/MRP assistance to facilitate efficient inventory
                    management accessible manually initially, by 11-1-1996.
               d.   PBMS will provide input to sales forecasting modules and
                    DRP/MRP system parameters to (i) facilitate efficient
                    inventory management and (ii) ensure product availability as
                    necessary.
               e.   PBMS and CellStar will work together to develop cost
                    effective production/assembly processes.

          4.3.4  CREDIT LINE ADMINISTRATION, ORDER PROCESSING AND FULFILLMENT
               a.   PBMS' Customer Care and Order Processing systems shall be
                    capable of accepting orders from Retailers and other
                    resellers, individual subscribers, and business Customers.
               b.   PBMS will determine and administer all Order processing
                    procedures, specific Customer Order packaging requirements,
                    pricing, sales and marketing relationships with its
                    Customers.
               c.   PBMS will pass Customer shipping instructions (including
                    without limitation, Order packaging and labeling
                    specifications), and billing information to CellStar
                    electronically through the PBMS Order Processing system, as
                    specified in the Procedures Manual, or in such other manner
                    used by PBMS to communicate the information.
               d.   CellStar shall generate a packing list for each Order.
               e.   CellStar will provide Retailer and other reseller credit
                    line administration for Orders received from PBMS.
                    Exceptions to credit lines may be approved by PBMS' Chief
                    Financial Officer or designate and PBMS assumes
                    responsibility for Customer credit risk with respect to such
                    approved exceptions.  CellStar assumes responsibility for
                    all other credit risk associated with the financial strength
                    of Retailers and other resellers invoiced by CellStar.  PBMS
                    shall be responsible for collection or repayment to CellStar
                    for customer deductions for allowances, fines, 

                                       7
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                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

                    penalties and other debits unrelated to traditional credit
                    risk. Notwithstanding the foregoing sentence, if PBMS in
                    good faith believes that any Customer deduction for
                    allowances, fines, etc. are the result of a CellStar error
                    in fulfilling CellStar's obligations under the applicable
                    Order and further believes that CellStar should assume the
                    burden of that deduction, then PBMS may present the issue to
                    the CPT for resolution.
               f.   CellStar shall provide all Fulfillment Services with respect
                    to Customer Orders.
               g.   CellStar will provide electronic confirmation to PBMS of all
                    shipments completed on behalf of PBMS including carrier
                    tracking codes by January 31, 1997.

          4.3.5  ACCOUNTS RECEIVABLE, INVOICING AND COLLECTIONS
               a.   PBMS will bill individual subscribers and business Customers
                    for its Direct Sales Accounts through PBMS' Customer Care
                    and Billing systems (CCBS).  Accordingly, PBMS will not
                    provide this type of billing information to CellStar.
               b.   CellStar will invoice Retailers and other resellers upon
                    Product shipment in accordance with PBMS' instructions
                    regarding the Customer's billing information as stated in
                    the applicable Order or, if not stated in the applicable
                    Order, as specified in the Procedures Manual.
               c.   CellStar will collect payments from Retailers and other
                    resellers.
               d.   CellStar will perform payment reconciliation with Retailers
                    and other resellers to assist PBMS in properly classifying
                    deductions and resolving disputes for unauthorized Customer
                    deductions from invoices.  PBMS will reimburse CellStar for
                    all Customer deductions (not associated with traditional
                    risk of creditworthiness), whether authorized or otherwise,
                    in accordance with PBMS' Deductions Policy.  PBMS shall
                    reimburse CellStar for any unresolved Customer deduction
                    that is outstanding for more than 180 days without regard of
                    the status of collection efforts.  Notwithstanding the
                    foregoing sentence, if PBMS in good faith believes that any
                    such Customer deduction arose from a CellStar error which
                    was in CellStar's control, in fulfilling CellStar's
                    obligations under the applicable Order, PBMS shall present
                    the issue to the CPT for resolution.  If PBMS reimburses
                    CellStar for a Customer deduction and CellStar subsequently
                    collects the deduction from the Customer, CellStar shall
                    immediately credit PBMS that amount.
               e.   CellStar will invoice PBMS for Products shipped to the
                    Customer  immediately following Product shipment to the
                    Customer.
               f.   Upon PBMS' request, CellStar will promptly provide
                    information to PBMS on each Customer's sales and credit
                    status.

                                       8
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                                                MASTER AGREEMENT NO. P/PS-960163

          4.3.6  INVENTORY ACCOUNTING AND CONTROL

               CellStar covenants and agrees to employ methods of inventory
               accounting and control that are in accordance with generally
               accepted accounting principles.

          4.3.7  MAINTENANCE OF BOOKS AND RECORDS

               CellStar covenants and agrees to maintain books and records
               covering all transactions under this Agreement and shall make
               such books and records available for PBMS' inspection at any
               time, including CPA auditors from a major accounting firm hired
               by or engaged by PBMS, by and through CellStar's representatives
               and agents, during regular business hours on any business day.

          4.3.8  INVENTORY/WAREHOUSING

               CellStar shall separately inventory and warehouse Dedicated
               Products from Open Stock.  CellStar shall designate an area for
               Dedicated Products in a separate secure area and in accordance
               with PBMS' instructions.

          4.3.9  RETURNS PROCESSING

               a.   CellStar will process Customer returns from Retailers and
                    other resellers, individual subscribers, and business
                    Customers through its J.D. Edwards system and PBMS' Customer
                    Care and Order Processing systems.
               b.   PBMS will be responsible for setting the appropriate
                    standard cost value of the A and B and discard stock items
                    in the inventory master file.  CellStar will determine the
                    value of the returned products based on the returns
                    procedures set forth in the Procedures Manual. CellStar will
                    bill PBMS for any inventory writedown from A to B or discard
                    stock value.

               c.   All Customer returns and vendor and product supplier
                    warranty procedures for the Products shall be in accordance
                    with the Procedures Manual.

          4.3.10  USE OF FICTITIOUS BUSINESS NAME

               a.   The parties understand and agree that CellStar will, for
                    certain purposes, need to use the name "Pacific Bell Mobile
                    Services Fulfillment" or such other substantially similar
                    name as CellStar is able to register as an assumed name in
                    the State of Texas and Dallas County, Texas (the "Name").
                    PBMS hereby authorizes CellStar to use the name for the
                    following purposes: (i) receipt and acceptance of payment
                    from Customers (including, without limitation, via lock-box
                    wire transfer or check), (ii) inclusion in shipping
                    collateral provided to Customers, (iii) invoicing of
                    Customers and provision of Customer statements, (iv) written
                    and oral correspondence with Customers, (v) such other
                    purposes 

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                    as are authorized in writing by PBMS and (vi) collection
                    activities; provided that any use of the Name by CellStar
                    shall be in accordance with the guidelines provided by PBMS
                    entitled "Four Basic Rules", incorporated by reference into
                    this Agreement. PBMS further authorizes CellStar to register
                    the Name with the Secretary of State of the State of Texas
                    and in Dallas County, Texas. CellStar's right to use the
                    Name is a nonexclusive right and PBMS shall retain all
                    ownership and intellectual property rights in the Name.
                    Except as provided herein, CellStar shall not use the Name
                    in any advertising or publicity matter without PBMS' prior
                    written consent.

               b.   Upon expiration, termination or cancellation of this
                    Agreement, CellStar may continue to use the Name only during
                    the period the Services are transitioned to PBMS or its
                    authorized contractor and for the purpose of receiving or
                    collecting remaining payments, if any, due CellStar from
                    Customers in connection with the Agreement (collectively,
                    the "Transition Period").  Upon the conclusion of the
                    Transition Period, and upon PBMS' request, CellStar shall
                    confirm in writing that it has ceased all use of the Name.

     4.4  COMPENSATION

          As detailed in Exhibits B and C, PBMS shall compensate CellStar for
          each of the following Service components:

          4.4.1  START-UP COSTS

               Upon execution of this Agreement, CellStar will invoice PBMS for
               the start-up costs set forth in Exhibit B.

          4.4.2  INVENTORY CARRYING COSTS

               A recurring charge, calculated and billed monthly as a "cost of
               capital" charged on [REDACTED]

          4.4.3  STANDARD PRODUCT COST

               CellStar shall invoice PBMS standard Product cost at the time of
               shipment as set forth in Section 7.a.  This cost represents the
               sum of all Product components and assembly costs including
               assembly charges, packaging and collateral materials and standard
               loss allowances as shown on the Product bill of materials.

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          4.4.4  CREDIT FOR CUSTOMER RECEIVABLE

               Following each shipment, CellStar will record a payable to PBMS
               for the value of the invoice to the Retailer or other reseller as
               set forth in Section 7.b.

          4.4.5  FULFILLMENT SERVICES COSTS

               A warehouse picking charge of [REDACTED] per carton shipped.

               An additional charge of [REDACTED] per Order picked from
                 Component Inventory.

               Actual transportation charges as billed by the carrier (the
                 discounted amount) for delivery to the Customer.

               Actual insurance charges covering loss or damage in transit.

          4.4.6  MONTHLY RECURRING SERVICE FEES

               The monthly service fees shall be comprised of the following
               components:

               a.   A monthly "cost of capital" charge predicated on [REDACTED]

               b.   A monthly Service fee for invoice processing and collection
                    Services predicated on the cost of such Services plus
                    margins as set forth in Exhibit C.

               c.   Non-recoverable returns and freight.

               d.   Such other items as set forth in Exhibit C.

          4.4.7  RETURNS

               See Procedures Manual.  See also Exhibit B for the fees to be
               billed to PBMS for skid storage fees and Products returned by
               Customers ("return fees").

          4.4.8  PURCHASE PRICE VARIANCES

               CellStar shall operate on the basis of a "standard cost"
               accounting system and shall invoice all Product cost at "standard
               cost" as noted in Section 4.4.3.  All purchase price variances
               for the account of PBMS shall be invoiced or credited to PBMS as
               of the close of each month.  Periodic changes in standard cost
               will generate a change in inventory valuation and corresponding
               debit or credit to Purchase Price Variances accounts.  These
               debits and credits to the Purchase Price Variances 

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               accounts for the account of PBMS shall be invoiced or credited by
               CellStar as of the close of each month.

     4.5  PBMS/SUPPLIER AGREEMENTS

          a.   PBMS has included in certain third party manufacturer or supplier
               agreements (hereinafter "PBMS/supplier agreements") with its PCS
               product suppliers (the "product suppliers") the right for a third
               party distributor, such as CellStar, to execute orders under the
               PBMS/supplier agreements for the purchase of PCS products.  As
               necessary and as permitted by nondisclosure agreements between
               PBMS and its suppliers,  PBMS agrees to provide CellStar a copy
               of the PBMS/supplier agreements (or pertinent extracts) in order
               for CellStar to order Dedicated Products only as PBMS may direct,
               and not for the purpose of ordering products for any of
               CellStar's other customers.  CellStar agrees to keep the terms of
               the supplier agreements strictly confidential and not to disclose
               the terms of the PBMS/supplier agreements, including pricing, to
               any third party, without PBMS' prior written consent, unless that
               third party has a legitimate need to know in the performance of
               services to CellStar, and is covered by an appropriate
               confidentiality agreement prior to accessing the Information.
               "Third parties" shall include without limitation, any potential
               competitors of the product suppliers, including competitors that
               are partners or third parties holding any form of equity interest
               in CellStar.

          b.   In addition to the above and subject to CellStar's rights under
               Section 4.2.1. above (regarding instances, if any, in which
               CellStar has notified PBMS that it cannot comply with a product
               supplier agreement prior to executing a CellStar Order), CellStar
               agrees to abide by all applicable terms and conditions of the
               PBMS/supplier agreements, including payment and confidentiality
               terms.  CellStar may not add any supplementary or conflicting
               terms to any CellStar Order under a PBMS/supplier agreement
               without PBMS' prior written consent.  The right to receive any
               liquidated damages, promotional monies or other such payments
               under a PBMS/supplier agreement shall belong exclusively to PBMS
               whether or not CellStar executed a CellStar Order for Dedicated
               Products in connection with the product supplier's payment of
               liquidated damages, promotional monies or other such payments.
               In the event the product supplier pays any such liquidated
               damages, promotional monies or other such payments to CellStar in
               connection with Dedicated Products, CellStar shall immediately
               transfer those funds to PBMS without set-off, administrative
               charge or deduction of any kind.

          c.   In connection with a CellStar Order for Dedicated Products under
               a PBMS/supplier agreement, if CellStar does not or, believes it
               cannot, make full payment to any product supplier within 30 days
               following product delivery by the product supplier under the
               applicable CellStar 

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               Order, CellStar shall notify PBMS immediately and provide
               information concerning the reason for the nonpayment.
               Notwithstanding the foregoing, CellStar agrees to make best
               efforts to make payment to the product suppliers when due and
               CellStar expressly acknowledges that failure to do so shall
               result in a material breach by CellStar of the terms of this
               Agreement, unless PBMS expressly waives CellStar's breach in
               writing. PBMS agrees that it shall not cure a breach of
               CellStar's payment obligations under a PBMS/supplier agreement
               unless and until such time that CellStar's 15 calendar day cure
               period (as described in Section 24 of this Agreement) has
               elapsed.

          d.   In the event that PBMS cures CellStar's default on any payment
               obligation to a product supplier under a CellStar Order issued
               pursuant to a PBMS/supplier agreement, CellStar shall with
               respect to that default:

               i)   TO THE EXTENT THAT CELLSTAR HAS PREVIOUSLY SHIPPED THE
                    PRODUCTS TO THE CUSTOMER:  CellStar shall immediately credit
                    PBMS' account in full for the money PBMS paid to the product
                    supplier (the "default amount").

               ii)  IN THE EVENT THAT THE PRODUCTS HAVE NOT YET BEEN SHIPPED TO
                    THE CUSTOMER:  CellStar shall automatically be deemed to
                    have sold the Products to PBMS upon the date, and in
                    consideration of, PBMS' payment to the product supplier.
                    Any subsequent shipment of such Products to Customers shall
                    be considered consignment inventory and Product costs shall
                    not be billed to PBMS, unless CellStar buys back the
                    Products from PBMS.

          e.   In the event that this Agreement expires or is terminated or
               canceled, any credits, including default amounts remaining in
               PBMS' account, shall be paid to PBMS in cash within thirty (30)
               days of such expiration, termination or cancellation date.
               Additionally, at any time, PBMS may set-off any PBMS payment due
               CellStar, by the amount of credits due PBMS.

5.   ORDERS

     CellStar's commencement of performance of any Order shall be deemed to be
     acceptance of such Order upon the terms  and  provisions of this Agreement.
     Any additional or different terms in any CellStar quotation,
     acknowledgment, invoice or other communication to PBMS, whether or not such
     terms materially alter an Order, shall be deemed objected to by PBMS
     without need of further notice of objection and shall be of no effect and
     not in any circumstance be binding upon PBMS unless expressly accepted by
     PBMS in writing.

     Subject to CellStar's rights set forth in the preceding paragraph, the
     parties expressly agree that all Orders electronically transmitted by PBMS
     to CellStar shall be deemed to constitute a "writing sufficient to indicate
     that a contract for sale has been made between 

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     the parties and signed by the party against whom enforcement is sought or
     by his authorized agent or broker" for purposes of section 2201 of the
     California Uniform Commercial Code. The parties further agree that data
     mechanically or electronically stored by PBMS or CellStar in the course of
     business shall constitute acceptable documentation of the contents of any
     Order or invoice electronically transmitted by either party to the other.

6.   PRICES

     Prices are set forth in Exhibit B and D.  [REDACTED] Prices changes and
     prices for any new Products or Services set forth in Exhibit B shall be
     implemented only when agreed to by the CPT. Additionally, the following
     shall apply:

     (i)   Any price changes for assembly costs as set forth in Section 1.c. of
     Exhibit B, shall be determined on the basis of the assembly cost model set
     forth in Exhibit F.
     (ii)  Assembly prices for all new Products set forth in Exhibit B,
     including price changes for  those Products, shall be determined on the
     basis of assembly cost model set forth in Exhibit F.
     (iii)  Any price changes for credit and collection Services as set forth in
     Section 3.c. of Exhibit B shall be determined on the basis of the component
     cost analysis set forth in Exhibit C.
     (iv)  Prices for any new administrative Services set forth in Exhibit B,
     including any price changes for those Services, shall be determined on the
     basis of component cost analysis similar to that set forth in Exhibit C.

7.   INVOICING AND PAYMENT

     a.   Promptly after shipment of Products to the Customer, CellStar shall
          render an invoice to PBMS for each such shipment.  The invoice shall
          identify and separately show quantities and prices for each item
          shipped and for Services provided any shipping charges to be borne by
          PBMS, applicable sales or use taxes, any discounts and total amount
          due.  PBMS shall promptly pay CellStar the amount due within one (1)
          business day after receipt of the invoice.  Both parties are currently
          working to develop EFT capabilities.  Until such time that EFT is
          implemented, PBMS will remit payment by wire transfer each Monday, for
          the prior week.
     b.   Promptly after the shipment of Products to the Customer, CellStar
          shall remit payment to PBMS in an amount that equals the invoiced
          amount generated by CellStar to the Retailer or other reseller.  Both
          parties are currently working to develop EFT capabilities.  Until such
          time that EFT is implemented, CellStar will remit payment by wire
          transfer each Monday, for the prior week.
     c.   Promptly after the performance of Services rendered, CellStar shall
          render an invoice electronically for such Services.  The invoice shall
          identify and separately show prices for the Services, including Cost
          of Capital.  PBMS shall promptly pay CellStar the amount due via
          electronic funds transfer ("EFT') within one (1) business day after
          receipt of the invoice.  Both parties are currently working to develop
          EFT capabilities.  Until such time that EFT is 

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<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

          implemented, PBMS will remit payment by wire transfer each Monday, for
          the prior week.
     d.   If PBMS disputes any invoice rendered or amount paid, PBMS shall so
          notify CellStar after payment, and the parties, through the CPT, shall
          use their best efforts to resolve such dispute expeditiously.  The CPT
          shall provide all pertinent information to PBMS and CellStar upon
          request to enable and cooperate with PBMS in investigating the amount
          in dispute.
     e.   With respect to Section 7.a. and b. above, upon agreement by both
          parties, amounts due for transactions under such Sections may be
          consolidated for the purpose of the single transfer of funds.  Nothing
          in this paragraph e. however, limits PBMS' right to set-off payments
          due CellStar as set forth in Section 4.5.e. of this Agreement.

8.   SHIPPING AND PACKING

     a.   CellStar shall ship all Orders to PBMS' Retailers and other resellers
          according to the specific shipping instructions for that Customer when
          set forth in the Procedures Manual, unless PBMS specifies other
          instructions in the applicable Order, provided that CellStar shall
          have had a reasonable opportunity to (i) review the applicable
          Customer's standard shipping instructions prior to receipt of such
          Order, and (ii) make arrangements to accommodate any special
          instructions of such Customer.  PBMS agrees to reimburse CellStar for
          additional freight charges, if any, required to satisfy such special
          instructions.  Whenever possible however, CellStar shall use the
          lowest priced shipping carrier (and where possible use a contract
          carrier) capable of shipping the Products on time.  In the event the
          Order contains other shipping instructions, then notwithstanding the
          section entitled "Order of Precedence" in this Agreement, the Order
          shall take precedence over the shipping instructions set forth in the
          Procedures Manual.
     b.   CellStar shall ship Products as specified in PBMS' Order to meet PBMS'
          specified shipment or arrival date.
     c.   Unless expressly stated to the contrary, CellStar's charges for
          transportation Services including, but not limited to, routing,
          transporting, hauling, hoisting, storage and detention, are not
          included in any prices furnished for Products.
     d.   Marking and labeling ("Marking") of packages may vary depending on
          Product and Order type.  Standard Markings shall include, but not be
          limited to, Markings which are or shall be required by applicable laws
          and regulations governing the environment and hazardous
          materials/wastes, Order number, container number, ship-to address,
          return address, Product identification, quantity, date packed and
          gross weight, where applicable.

9.   TAXES

     a.   PBMS shall reimburse CellStar the cost of all sales and use taxes and
          import and export duties, and other governmental fees to the extent
          related to PBMS' Orders not otherwise included in the invoice for the
          original shipment to PBMS Customers.
     b.   CellStar agrees to pay, and to hold PBMS harmless from and against,
          any penalty, interest, additional tax or other charge that may be
          levied or assessed as 

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          a result of the delay or failure of CellStar for any reason to pay any
          tax or file any return or information required by law, rule or
          regulation or by this Agreement to be paid or filed by CellStar.
     c.   If  PBMS is exempt from payment of any applicable sales and/or use tax
          upon notifying CellStar of the basis for claiming such exemption
          CellStar agrees to take all legal and proper steps to sell the
          Products free of sales and/or use tax or to act as PBMS' agent in
          applying for any applicable rebate of tax.  PBMS will, upon request
          furnish CellStar with any applicable tax exemption number.

10.  RECORDS AND AUDITS

     CellStar shall maintain accurate records of all matters which relate to
     CellStar's obligations hereunder in accordance with generally accepted
     accounting principles and practices, uniformly and consistently applied in
     a format that will permit audit.  Unless otherwise provided in this
     Agreement, CellStar shall retain such records for a period of four (4)
     years from the date of final payment under the Order to which such records
     relate.  To the extent that such records may be relevant in determining if
     CellStar is complying with its obligations under the applicable Order, PBMS
     and its authorized representatives shall, at any time, upon reasonable
     advance notice, have access to such records for inspection and audit during
     normal business hours.

11.  INDEPENDENT CONTRACTOR

     CellStar hereby declares and represents that CellStar is engaged in an
     independent business and will perform its obligations under this Agreement
     as an independent contractor and not as the agent or employee of PBMS; that
     the persons performing services hereunder are not agents or employees of
     PBMS; that CellStar has and hereby retains the right to exercise full
     control of and supervision over the performance of CellStar's obligations
     hereunder and full control over the employment, direction, compensation and
     discharge of all employees assisting in the performance of such
     obligations; that CellStar shall be solely responsible for all matters
     relating to payment of such employees, including compliance with workers'
     compensation, unemployment, disability insurance, social security,
     withholding and all other federal, state and local laws, rules and
     regulations governing such matters; and that CellStar shall be responsible
     for CellStar's own acts and omissions and those of CellStar's agents,
     employees and contractors during the performance of CellStar's obligations
     under this Agreement.

12.  NONEXCLUSIVE AGREEMENT

     This Agreement is a nonexclusive agreement.  PBMS expressly reserves the
     right to contract with others for any of the products or services it may
     require.  PBMS also reserves the right, at any time, to 1) bring any of the
     Services described under this Agreement in-house or 2) enter into an
     arrangement whereby a PBMS Affiliate provides the types of Services
     described hereunder.

13.  INDEMNIFICATION

     CellStar shall indemnify, defend and hold harmless PBMS and its Affiliates,
     and the directors, shareholders, agents and employees of any of them
     ("Indemnitees"), from and against any fine, penalty, loss, cost, damage,
     injury, claim, expense or liability, including 

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     attorney's fees and court costs (individually and collectively
     "Liabilities"), as a result of (i) injury to or death of any person; (ii)
     damage to, loss or destruction of any property; (iii) failure to comply
     with the section entitled "Compliance with Laws", or (iv) breach of a
     PBMS/supplier agreement where such Liabilities arise out of CellStar's
     performance of this Agreement except for that portion of Liabilities which
     are caused by PBMS' negligence or willful misconduct. CellStar shall (1)
     keep PBMS and any PBMS Indemnitees subject to such Liabilities fully
     informed as to the progress of the defense and/or settlement and (2) afford
     PBMS or any Indemnitee, each at its own expense, an opportunity to
     participate on an equal basis with CellStar in the defense or settlement of
     any such Liabilities.

     With respect to any claim of infringement of any patent, copyright, trade
     secret or other intellectual property right of any third party in
     connection with Open Stock, CellStar shall pass through to PBMS the
     manufacturer's and/or vendor's indemnity in connection with such
     infringement claim to the extent allowed by that manufacturer or vendor.
     With respect to any claim of infringement of any patent, copyright, trade
     secret or other intellectual, proprietary right of any third party in
     connection with Dedicated Products, PBMS shall pass through to CellStar the
     product supplier's indemnity in connection with such infringement claim, to
     the extent allowed by that product supplier.

     While PBMS is on CellStar's premises, PBMS agrees to indemnify CellStar
     under the same terms as set forth in paragraph a. above, for Liabilities as
     a result of any injury to or death of any person or damage, loss or
     destruction of any property which arises from PBMS' negligence or willful
     misconduct except for that portion of Liabilities which are caused by
     CellStar's negligence or willful misconduct.  In addition, PBMS agrees to
     indemnify CellStar under the same terms as set forth in paragraph a. above
     for Liabilities as a result of failure to comply with the Section entitled
     "Compliance With Laws" which arise out of PBMS' performance of this
     Agreement.

     PBMS agrees to indemnify, defend and hold harmless CellStar and its
     affiliates, and the directors, stockholders, agents and employees of any of
     them, from and against any Liabilities that arise in connection with
     CellStar's use of the Name, except to the extent such Liabilities are due
     to CellStar's negligence or misconduct.

14.  INSURANCE

     Any and all insurance, including Worker's Compensation Insurance, that may
     be required under the laws, ordinances, and regulations of any governmental
     authority, with respect to CellStar's performance under this Agreement, is
     and shall be the sole responsibility of CellStar.

     a.   Without in any way limiting CellStar's indemnification obligations
          hereunder, CellStar shall maintain the following insurance:

          i)  Commercial General Liability (Bodily Injury and Property Damage)
               Insurance including the following supplementary coverages:
               1.   Contractual Liability to cover liability assumed under this
                    Agreement;
               2.   Personal Injury Liability;

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               3.   Product and Completed Operations Liability Insurance;
               4.   Property Damage Liability Insurance;

          ii)  Business Automobile Liability Insurance if any of CellStar's
               employee owned, leased, hired or borrowed automobiles are used in
               the performance of this Agreement.  Coverage shall be in force
               for all owned, non-owned and hired automobiles used by CellStar.

          iii) The limit of the liability for insurance required above shall
               not be less than two million dollars ($2,000,000) combined single
               limit per occurrence.

     b.  The insurance specified above shall:

          i)   Name PBMS, its Affiliates, directors, agents and employees as
               additional insureds in matters covered by this Agreement, at
               CellStar's sole expense;
          ii)  Provide that such insurance is primary coverage with respect to
               all insureds;

          iii) Contain a Standard Cross Liability Endorsement which provides
               that the liability insurance applies separately to each insured
               and that the policies cover claims or suits by one insured
               against the other;

          iv)  Contain a waiver of subrogation and an assignment of statutory
               lien against PBMS for purposes of Worker's Compensation
               Insurance;

          v)   Include a requirement that the insurer provide PBMS with thirty
               (30) days written notice to PBMS prior to the effective date of
               any cancellation or material change of the policy or policies of
               insurance;

          vi)  have insurance issued by insurance companies that hold a current
               rating of not less than A/XV, according to Best's Key Rating
               Guide.

     c.   If requested by PBMS, CellStar shall provide PBMS with a Certificate
          of Insurance executed by a duly authorized representative of the
          insurer evidencing the coverages, limits, and provisions specified
          above.
     d.   If CellStar's insurance is on "claims-made" forms, CellStar's
          obligations to maintain the insurance and to provide policy
          endorsements required herein shall survive the termination of this
          Agreement for a period of five (5) years.

15.  ACCESS

     a.  PBMS' Premises

          CellStar shall when appropriate have reasonable access to PBMS'
          premises during normal business hours and at such other times as may
          be agreed upon by the parties in order to enable CellStar to perform
          its obligations under this Agreement.  CellStar shall coordinate such
          access with PBMS' designated representative prior to visiting such
          premises.  If PBMS for any lawful reason requests CellStar to
          discontinue furnishing any person provided by CellStar for performing
          work on PBMS' premises, CellStar shall immediately comply with such
          request.  Such person shall leave PBMS' premises promptly and CellStar

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          shall not furnish such person again to perform work on PBMS' premises
          without PBMS' prior consent.

     b.  CellStar's Premises

          PBMS shall, upon reasonable prior notice to CellStar and at no
          additional charge, have reasonable access to CellStar's premises
          during normal business hours in order to observe CellStar's work with
          respect to the Products and Services or to take possession of any
          Dedicated Products paid for by PBMS. If CellStar for any lawful reason
          requests PBMS to discontinue furnishing any person provided by PBMS
          for performing work on CellStarOs premises, PBMS shall immediately
          comply with such request.  Such person shall leave CellStarOs premises
          promptly and PBMS shall not furnish such person again to perform work
          on CellStarOs premises without CellStarOs prior consent.

     c.  Rules and Regulations

          The employees and agents of CellStar and PBMS shall, while on the
          premises of the other, comply with all site rules and regulations,
          including, where required by government regulations, submission of
          satisfactory clearance from the U.S. Department of Defense and other
          governmental authorities concerned.

     d.  Releases Void

          Neither party shall require waivers or releases of any personal rights
          from representatives of the other in connection with visits to its
          premises, and no such releases or waivers shall be pleaded by either
          party in any action or proceeding.

16.  INFORMATION

     a.   In the performance of its obligations under this Agreement, either
          party may receive or access (the Oreceiving partyO) Information from
          the other party (the Odisclosing partyO).  Such Information may
          contain material which is proprietary or confidential, disclosures of
          patentable inventions with respect to which patents may not have been
          issued or for which patent applications may not have been filed, or
          material which is subject to applicable laws regarding secrecy of
          communications or trade secrets.  Accordingly, the receiving party
          agrees:

          i)   that all such Information so acquired by it or its employees,
               contractors or agents (individually and collectively "personnel")
               hereunder shall be and shall remain the disclosing party's
               exclusive property;
          ii)  to inform all of its personnel engaged in handling such
               Information of the proprietary or confidential character of such
               Information and of the existence of applicable laws regarding
               secrecy of communications;
          iii) to limit access to such Information to its personnel having a
               need to know;
          iv)  to keep, and have its personnel who receive or access such
               Information keep, such Information confidential;
          v)   to return promptly or certify that it has destroyed, any copies
               of such Information in written, graphic or other tangible form
               upon the disclosing partyOs request; and
          vi)  to use such Information only for purposes of this Agreement and
               for other purposes only upon such terms as may be agreed upon
               between the parties in writing.

                                       19
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
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                                                MASTER AGREEMENT NO. P/PS-960163

     b.   Notwithstanding the foregoing, nothing contained in this Section 16
          shall restrict either party in the use or disclosure of any
          Information from the other party which:
          i)   is already in such party's possession without accompanying use or
               disclosure restrictions prior to its receipt from the other
               party; or
          ii)  is or subsequently becomes publicly available through no fault of
               such party; or
          iii) is rightfully received by such party from a third party without
               accompanying use or disclosure restrictions; or
          iv)  is independently developed by such party or a third party without
               the aid, application or use of any Information received pursuant
               to this Agreement; or
          v)   is approved in writing for release by the other party.

     c.   Each party hereto acknowledges and agrees that in the event of the
          violation of this Section 16, irreparable damage may occur, and
          therefore the aggrieved party shall be entitled to seek court ordered
          injunctive relief to halt the violation of this Agreement which such
          remedy shall be in addition to any other remedies available to the
          aggrieved party at law or in equity.

     d.   If either party is required by law or by governmental regulation or
          rule or receives a request to disclose all or any part of the
          disclosing party's Information by applicable law or, under the terms
          of a subpoena or other order issued by a court of competent
          jurisdiction or by a government agency, the receiving party shall:
          (i) promptly notify the disclosing party of the existence, terms and
          circumstances surrounding any such requirement or request; (ii)
          consult with the disclosing party regarding the advisability of taking
          steps to resist or narrow such requirement or request; (iii) if
          disclosure of such Information is required, furnish only such portion
          of the Information as the receiving party is advised by counsel is
          legally required to be disclosed; and (iv) cooperate with the
          disclosing party, at the disclosing party's expense, in its efforts to
          obtain an order or other reliable assurance that confidential
          treatment will be accorded to that portion of the Information that is
          required to be disclosed.

17.  QUALITY

     a.   PBMS and CellStar believe that benefits accrue to both parties when
          they cooperate to improve quality and to control costs.
     b.   CellStar shall be engaged in on-going quality improvement efforts and
          practices which are consistent with the latest standards and practices
          in the industry.
     c.   CellStar shall maintain a quality assurance system designed to
          identify, correct and prevent deficiencies.
     d.
          i)   CellStar agrees to perform all quality control functions in
               conformance with the "Warranties" section of the Agreement, the
               Specifications and applicable Order; and, in the absence of
               Specifications, to good commercial practice.  Detailed inspection
               records, documentation and 

                                       20
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                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
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                                                MASTER AGREEMENT NO. P/PS-960163

               other data relating to CellStar's standards in effect at
               CellStar's premises shall be maintained by and made available to
               PBMS upon request.
          ii)  At PBMS' option, PBMS may at all reasonable times and places,
               either perform or observe CellStar performance of inspections and
               tests of any Products pertaining to the Agreement.  CellStar
               shall designate, at each of CellStar's applicable distribution
               facilities, one (1) or more responsible employees with whom PBMS
               may discuss any matters relating to Product quality and
               reliability.  CellStar shall also make available to PBMS at no
               additional charge, such facilities, data, Specifications and
               information regarding CellStar procedures and any other
               documents, information and assistance as may be deemed reasonably
               necessary by PBMS to perform inspections and tests related to
               CellStar's Product handling and as mutually agreed by the CPT in
               writing.
          iii) PBMS may inspect and test Products, in whole or in part, prior
               to or subsequent to final assembly and/or completion of Product
               manufacturing or repair processes.  Whenever Products are made
               available to PBMS for inspection and testing, CellStar shall also
               make available to PBMS copies of any Order(s) applicable to such
               Products.  Whenever CellStar establishes a stock of Products to
               be shipped to PBMS or its Customers pursuant to Orders to be
               issued by PBMS in the future, such Products shall be available
               for inspections by PBMS prior to delivery by CellStar.
          iv)  PBMS' exercise of, or failure to exercise, the rights provided in
               this Section shall not relieve CellStar of its obligation to
               furnish all Products in conformance to this Agreement and the
               applicable Order.

18.  REGISTRATION

     To the extent that PBMS purchases Open Stock, CellStar represents that,
     from the date of this Agreement on a going forward basis, it will use its
     best reasonable efforts to include in its contracts with each manufacturer
     that provides Open Stock to CellStar, the manufacturer's commitment and
     obligation to comply with all Federal Communications Commission's Rules and
     Regulations as may be amended from time to time, including, but not limited
     to, all labeling and Customer instruction requirements with respect to that
     Open Stock.   CellStar agrees to indemnify PBMS for any Liabilities
     pursuant to the Section entitled "Indemnification" of this Agreement for
     CellStar's breach of this Section entitled "Registration".  PBMS agrees
     that it will use its best reasonable efforts to include in its contracts
     with each product supplier that provides Dedicated Products to CellStar the
     product supplier's commitment and obligation to comply with all Federal
     Communication Commission's rules and regulations as may be amended from
     time to time, including but not limited to all labeling and Customer
     instruction requirements with respect to that Dedicated Product.  PBMS
     agrees to indemnify CellStar for any Liabilities pursuant to the Section
     entitled "Indemnification" of this Agreement for PBMS' breach of this
     Section entitled "Registration".

                                       21
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                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
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                                                MASTER AGREEMENT NO. P/PS-960163

19.  INSIGNIA

     Upon PBMS' written request, Insignia shall be properly affixed by CellStar
     to the Products furnished.  Such Insignia shall not be affixed, used or
     otherwise displayed on the Products furnished or in connection therewith
     without PBMS' written approval.  The manner in which such Insignia will be
     affixed must be approved in writing by PBMS.  If PBMS directs CellStar to
     remove Insignia from any Products rejected or not purchased by PBMS,
     CellStar shall do so at a price to be negotiated by the CPT for such
     removal.

20.  HAZARDOUS MATERIALS

     a.   CellStar shall notify PBMS in writing at least thirty (30) days prior
          to shipment when any Open Stock Product or Services or processes
          consists of or contains a "hazardous chemical substance or mixture" or
          a "hazardous and/or radioactive material", as these terms are defined
          in all applicable federal, state and local laws, regulations and
          orders ("Regulations").
     b.   Any hazardous materials in Products or Services provided hereunder by
          CellStar shall be transported or handled in accordance with the
          requirements of the applicable Regulations including, but not limited
          to, those of the Department of Transportation governing transportation
          of such hazardous materials.

21.  CODES, LAWS OR REGULATIONS

     CellStar shall make any changes to its Services and will use its best
     efforts to cause the manufacturers of Open Stock to change the Open Stock
     and PBMS will use its best efforts to cause the product suppliers of
     Dedicated Products to change the Dedicated Products, in order to meet
     codes, laws or regulations which are in effect.

22.  NOTICE OF DELAYS

     Whenever any actual or potential cause delays or threatens to delay
     CellStar's performance, CellStar shall immediately so notify PBMS in
     writing.  Such notice shall include all relevant information concerning the
     actual or potential cause of the delay and its background.  During the
     period such actual or potential cause exists, CellStar shall keep PBMS
     advised of its effect on CellStar's performance and of the measures being
     taken to remove it.

23.  CHANGES AND SUSPENSIONS

     a.   Subject to Section 48 below, PBMS may, by notice to CellStar, suspend,
          in whole or in part, the delivery of Products and the performance of
          Services or any Order.  If PBMS directs any such change or suspension,
          the parties shall agree to any adjustments in prices or dates
          necessitated thereby and shall execute a revised Order reflecting such
          adjustments.
     b.   Subject to Section 40 below, CellStar may not, without PBMS' prior
          written consent, make any changes whatsoever with respect to the
          Products or Services specified in any Order hereunder.

                                       22
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                       Not for Use or Disclosure Outside
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                                                MASTER AGREEMENT NO. P/PS-960163


24.  TERMINATION AND CANCELLATION

     a.   Default
          If either party is in material default of any of its obligations under
          this Agreement and such default continues for fifteen (15) calendar
          days after written notice thereof is given by the party not in
          default, such nondefaulting party may cancel this Agreement and/or any
          Orders which may be affected by such default.

          The parties acknowledge that the first 180 calendar days of this
          Agreement will involve prototype development and process refinement
          and that breaches which are immaterial in nature with respect to such
          efforts shall not constitute a default which shall allow the other
          party to cancel this Agreement, unless however the default is ongoing
          and the defaulting party does not take reasonable steps within 60
          calendar days following notice of the breach, to eliminate the
          default.

          Default may include any of the following Events of Default which would
          allow the nondefaulting party to cancel this Agreement and/or any
          Orders immediately:

          i)   Termination of Business, Bankruptcy, Etc.  Either party shall
               -----------------------------------------                    
               cease its operations or sell or otherwise dispose of all or
               substantially all of its assets or there shall be change in
               ownership of either party's business, an assignment for the
               benefit of creditors, insolvency, appointment of a receiver or
               the filing of any petition under bankruptcy or debtor's relief
               laws of, or against either party.
          ii)  Material Adverse Change  Either party shall have reasonably
               -----------------------                                    
               determined that since the Effective Date, a Material Adverse
               Change has occurred with respect to the other party.
          iii) Representations and Warranties  Any warranty, representation or
               ------------------------------                                 
               certification made by either party or any officer of either party
               in this Agreement or in any document executed and delivered by
               either party in connection therewith shall be untrue in any
               material respect, in any case, on any date as of which the facts
               set forth are stated or certified.

     b.   Termination
          Provisions for termination of Orders hereunder are set forth in
          Section 48 of this Agreement.

25.  PARTIAL TERMINATION OR CANCELLATION

     Subject to Section 48, where a provision of this Agreement or applicable
     law permits PBMS to terminate or cancel an Order, such termination or
     cancellation may, at PBMS' option, be either complete or partial.  Subject
     to Section 48, in the case of a partial termination or cancellation PBMS
     may, at its option, accept a portion of the Products or Services covered by
     an Order and pay CellStar for such Products or Services at the prices set
     forth in such Order and the parties shall execute a revised Order to
     reflect such partial termination or cancellation.  The right to cancel an
     Order shall also include the right to cancel any other affected Order.

                                       23
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                       Not for Use or Disclosure Outside
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                        Except Under Written Agreement
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                                                MASTER AGREEMENT NO. P/PS-960163

26.  NONASSIGNMENT

     Except as otherwise provided by law, neither party shall assign its rights
     or delegate its duties ("Assignment") under this Agreement, without the
     prior written consent of the other party, which consent shall not be
     unreasonably withheld.  Any attempted Assignment or delegation of duties in
     contravention of this section shall be void and of no effect.  This
     Agreement shall inure to the benefit of and be binding upon the respective
     successors and assigns, if any, of CellStar and PBMS.  The assigning party
     shall provide thirty (30) days prior written notice to the other party of
     any proposed  Assignment.

27.  NOTICES

     Except as otherwise provided in this Agreement, or applicable Order, all
     notices or other communications hereunder shall be deemed to have been duly
     given when made in writing and either 1) delivered in person, 2) delivered
     to an agent, such as an overnight or similar delivery service, or 3)
     deposited in the United States Mail, postage prepaid,  and addressed as
     follows:

     To:  CELLSTAR, LTD.
          1730 Briercroft Court
          Carrollton, TX  75006
          Attn.: General Counsel

     To:  PACIFIC BELL MOBILE SERVICES
          4410 Rosewood Dr. Bldg. 1, 4th Floor
          Pleasanton, CA  94588
          Attn.: Director - Procurement

     The address to which notices or communications may be given by either party
     may be changed by written notice given by such party to the other pursuant
     to this paragraph entitled "Notices".

28.  PUBLICITY

     CellStar shall not use PBMS' or PBMS' Customers' or manufacturers' names or
     any language, pictures or symbols which could, in PBMS' judgment, imply
     their identity in any a) written or oral advertising or presentation or b)
     brochure, newsletter, book, or other written advertising material of
     whatever nature, without PBMS' prior written consent.  PBMS shall not use
     Open Stock manufacturers' names or any language, pictures, or symbols which
     could, in CellStar's judgment, imply their identity in any a) written or
     oral advertising or presentation or b) brochure, newsletter, book or other
     written advertising material of whatever nature, without CellStar's prior
     written consent.

29.  COMPLIANCE WITH LAWS

     Each party shall comply with all applicable federal, state and local laws,
     regulations and codes, including, but not limited to, the procurement of
     permits, certificates and licenses when needed in the performance of this
     Agreement.
                         PROPRIETARY AND CONFIDENTIAL

                                       24
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                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

30.  TITLE

     Unless otherwise provided in this Agreement, title to Dedicated Products
     shall vest in CellStar when the Products have been delivered by the product
     suppliers or manufacturers to CellStar's destination.

31.  NO THIRD PARTY BENEFICIARIES

     This Agreement is for the benefit of PBMS and CellStar and not for any
     other person.

32.  AMENDMENTS AND WAIVERS

     This Agreement may be amended or modified only by a written document signed
     by authorized representatives of both parties. No course of dealing or
     failure of either party to strictly enforce any term, right or condition of
     this Agreement shall be construed as a general waiver or relinquishment of
     such term, right or condition. Waiver by either party of any default shall
     not be deemed a waiver of any other default.

33.  EXECUTIVE ORDERS

     Exhibit A entitled "Exhibit A - Executive Orders and Associated
     Regulations" is attached hereto and made a part hereof.  As used in Exhibit
     A "Contractor" shall mean CellStar.

34.  HEADINGS

     Article, section, or paragraph headings contained in this Agreement are for
     reference purposes only and shall not affect the meaning or interpretation
     of this Agreement.

35.  GOVERNING LAW

     This Agreement and each Order shall be construed in accordance with the
     domestic laws (including the Uniform Commercial Code) but not the rules
     governing conflicts of law, of the State of California. To the extent that
     an Order involves the performance of Services, such Services shall be
     deemed to be "goods" within the meaning of the California Uniform
     Commercial Code.

36.  REMEDIES CUMULATIVE

     Except to the extent of any conflict with the section entitled "Limitation
     of Liability", any rights of cancellation, termination, or other remedies
     prescribed in this Agreement are cumulative and are not intended to be
     exclusive of any other remedies to which the injured party may be entitled,
     including but not limited to, the remedies of specific performance and
     cover, however, neither party shall retain the benefit of inconsistent
     remedies. Notwithstanding the foregoing, the remedy of specific performance
     shall apply only in the event of breach of 1) Section 16.c, 2) CellStar's
     obligation to sell Dedicated Products only to PBMS' Customers (unless
     otherwise permitted by PBMS), and 3) Section 52.

37.  SEVERABILITY

     If any provision or any part of a provision of this Agreement shall be
     invalid or unenforceable, such invalidity or unenforceability shall not
     invalidate or render unenforceable any other portion of this Agreement.

                                       25
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                       Not for Use or Disclosure Outside
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                        Except Under Written Agreement
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                                                MASTER AGREEMENT NO. P/PS-960163

38.  SURVIVAL

     Provisions contained in this Agreement that by their sense and context are
     intended to survive completion of performance, termination or cancellation
     of this Agreement shall so survive.

39.  PATENTS

     No licenses, express or implied, under any patents are granted by either
     party to the other party hereunder.

40.  FORCE MAJEURE

     a.   Neither party shall be deemed in default of this Agreement or any
          Order hereunder to the extent that any delay or failure in the
          performance of its obligations results from any cause beyond its
          reasonable control and without its fault or negligence, due to acts of
          God, disruption of telecommunications links, acts of civil or military
          authority, embargoes, epidemics, war, riots, insurrections, fires,
          explosions, earthquakes, floods, unusually severe weather conditions
          or strikes.
     b.   If any force majeure condition occurs, the affected party shall give
          immediate notice to the other party and the other party may elect to:
          (1) terminate the affected Order(s) or any part thereof, (2) suspend
          the affected Order(s) or any part thereof for the duration of the
          force majeure condition, with the option to obtain elsewhere products
          and services to be furnished under such Order(s) and deduct from any
          commitment under such Order(s) the products and services obtained or
          for which commitments have been made elsewhere or (3) resume
          performance under such Order(s) once the force majeure condition
          ceases with an option in the notified party to extend any affected
          delivery or performance date up to the length of time the force
          majeure condition endured.  Unless the notified party gives written
          notice within thirty (30) days after being notified of the force
          majeure condition, (2) shall be deemed selected.

41.  SUBCONTRACTING PLAN

     CellStar shall adopt and comply with the Exhibit(s) entitled Prime
     Contractor MBE/WBE/DVBE Job Specific Subcontracting Plan and/or Prime
     Contractor MBE/WBE/DVBE Commodity Product Subcontracting Plan, attached
     hereto and made a part hereof.

42.  MBE/WBE/DVBE CANCELLATION CLAUSE

     a.   If CellStar has represented itself or one of its subcontractors as a
          minority- or women-owned business or disabled veteran business
          enterprise:  CellStar agrees that falsification or misrepresentation
          of, or failure to report a disqualifying change in, the MBE/WBE/DVBE
          status of CellStar or any subcontractor utilized by CellStar; or
          CellStar's failure to comply in good faith with any MBE/WBE/DVBE
          utilization goals established by CellStar's Subcontracting Plan; or
          CellStar's failure to cooperate in any investigation conducted by
          PBMS, or by PBMS' agent, to determine CellStar's compliance with this
          section, will constitute a material breach of this Agreement.  In the
          event of any such breach, 

                                       26
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                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

          PBMS may, at its option, cancel this Agreement; and CellStar waives
          all claims related to such cancellation.
     b.   As used in this Agreement, Minority and Women Business Enterprises
          (MBEs/WBEs) are defined as businesses which are certified by the
          California Public Utilities Commission Clearinghouse to be 51% owned
          and operated by a minority individual or group or by one or more
          women; for publicly-held businesses, at least 51% of the stock must be
          owned by one or more minorities or women who are U.S. citizens or
          legal aliens with permanent residence status.  In each case, the
          management and daily operations must be controlled by one or more of
          those individuals.  Foreign-owned firms operating in the United States
          are not included in these definitions.

          For the purposes of this definition, minority group members include
          male or female Asian Americans, Black Americans, Filipino Americans,
          Hispanic Americans, Native Americans (i.e., American Indians, Eskimos,
          Aleuts and Native Hawaiians), Polynesian Americans, and multi-ethnic
          (i.e., any combination of MBEs and WBEs where no one specific group
          has a 51% ownership and control of the business, but when aggregated,
          the ownership and control combination meets or exceeds the 51% rule).
          "Control" in this context means exercising the power to make policy
          decisions.  "Operate" in this context means actively involved in the
          day-to-day management of the business.

          Disabled Veteran Business Enterprises (DVBEs) are defined as business
          concerns certified as DVBEs by the California   State Office of Small
          and Minority Business (OSMB).  The DVBE must be: (1) a sole
          proprietorship at least 51% owned by one or more disabled veterans; or
          (2) a publicly-owned business in which at least 51% of the stock is
          owned by one or more disabled veterans; or (3) a subsidiary which is
          wholly owned by a parent corporation, but only if at least 51% of the
          voting stock of the parent corporation is owned by one or more
          disabled veterans; or (4) a joint venture in which at least 51% of the
          joint venture's management and control and earnings are held by one or
          more disabled veterans.

          In each case the management and control of the daily business
          operations are by one or more disabled veterans.  For the purpose of
          this definition, a disabled veteran is a veteran of the military,
          naval or air service of the United States with a service-connected
          disability who is a resident of the State of California.

43.  DELIVERY OF PRODUCTS AND PERFORMANCE OF SERVICES

     a.   All dates for shipment or delivery of Products and performance of
          Services are firm and time is of the essence.  Shipment or delivery
          dates shall be specified in each Order.  (i)  In the event CellStar
          fails to meet the scheduled delivery date set forth in the applicable
          Order and the Customer cancels the Order, CellStar agrees to assume
          return shipping costs for the canceled Products if the late delivery
          was due to CellStar's error.    (ii) In the event CellStar fails to
          meet the scheduled delivery date set forth in the applicable Order but
          the Customer nonetheless accepts the late shipment, CellStar shall, if
          the CPT 

                                       27
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                                                MASTER AGREEMENT NO. P/PS-960163

          agrees, assume liability for any deductions taken by that Customer in
          connection with the late shipment if the late shipment was due to
          CellStar's error and within CellStar's reasonable control.
     b.   Notwithstanding anything to the contrary herein, PBMS understands and
          agrees that CellStar shall not be responsible for same day shipping
          unless CellStar receives the applicable Order by 3:00 pm, Central
          Standard Time on the shipment date.

44.  USE OF CELLSTAR'S PUBLISHED SPECIFICATIONS

     CellStar shall, at no charge, provide PBMS with copies of CellStar's
     published Specifications, user instructions, manuals and other training
     materials pertaining to the Products and Services purchased hereunder.
     PBMS shall have the right to reproduce any and all of such materials as
     necessary for PBMS' use of such Products.

45.  DOCUMENTATION

     Each party shall furnish to the other at no charge, mutually agreeable
     documentation, and any succeeding changes thereto, as described herein.
     PBMS may reproduce such documentation for use hereunder.

46.  RISK OF LOSS

     Subject to the following sentence, CellStar will be responsible for risk of
     physical loss of or damage to all inventories in their facilities and
     during shipment to the destination specified in the applicable Order, until
     such time that PBMS' Customer signs the carrier's receipt for the delivery.
     CellStar shall secure and prepay cartage insurance on behalf of the
     Customer and bill the Customer for such cartage insurance.

47.  WARRANTIES

     Services
     a.   CellStar warrants to PBMS that the Services provided hereunder shall
          be performed in a fully workmanlike manner to PBMS' reasonable
          satisfaction and in accordance with the Specifications set forth in
          this Agreement and the applicable Order.  CellStar further warrants
          that such Services shall be free from material defects in workmanship.
          This warranty shall survive inspection, acceptance and payment for a
          period of one (1) year.
     b.   If during the term hereof, PBMS believes that there is a breach of
          warranty as described herein, PBMS shall notify CellStar, setting
          forth in writing the nature of such claimed breach.  CellStar shall
          promptly investigate such breach and advise PBMS of CellStar's planned
          corrective action.  Thereafter, CellStar shall either repair or
          replace the affected Product, in CellStar's sole discretion.  If such
          breach of warranty has not been corrected within a reasonable time
          (not to exceed five (5) business days from PBMS' notice to CellStar of
          the breach) or if two (2) or more such breaches of warranty occur
          within any thirty (30) day period, PBMS may, in addition to all other
          rights and remedies provided by law or this Agreement, cancel the
          Order for the Services affected by such breach.

                                       28
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48.  TERMINATION OF ORDERS

     Services
     PBMS may terminate any Order covering the Services as described in Exhibit
     C and this Agreement, upon 90 calendar days written notice to CellStar.
     PBMS may terminate any other Order for other types of Services upon
     immediate notice. In the event of such termination, PBMS shall pay to
     CellStar the reasonable cost for such Services as set forth in Exhibit B
     and C, incurred by CellStar up to the date of said termination. PBMS shall
     not be responsible for the cost of any work performed by CellStar after
     such termination, nor for any costs incurred by CellStar's subcontractors
     which CellStar could have reasonably avoided. In no case shall termination
     costs exceed the amount, if any, agreed upon in the applicable Order for
     such Services. CellStar shall credit or reimburse PBMS for payments made by
     PBMS prior to termination to the extent such payments exceed the cost of
     work performed by CellStar, up to CellStar's receipt of the notice of
     termination.

49.  ALTERNATE DISPUTE RESOLUTION

     a.   If a controversy or claim should arise, a PBMS project representative
          and a project representative of CellStar, or their respective
          successors in the positions they now hold (herein called the "project
          representatives"), will meet in a mutually convenient location, at
          least once, and will attempt to, and are empowered to resolve the
          matter. Either project representative may request the other to meet
          within fourteen (14) days, at a mutually agreed time.
     b.   If the matter has not been resolved within twenty-one (21) days of
          their first meeting, the project representatives shall refer the
          matter to a PBMS senior executive, who shall have full authority to
          settle the dispute with a senior executive of CellStar.  Thereupon,
          the project representatives shall promptly prepare and exchange
          memoranda stating the issues in dispute and their positions,
          summarizing the negotiations which have taken place, and attaching
          relevant documents.  The senior executives will meet for negotiations
          within fourteen (14) days of the end of the twenty-one (21) day period
          referred to above, at a mutually agreed time.
     c.   The first meeting shall be held at the offices of the project
          representative receiving the request to meet.  If more than one
          meeting is held, the meetings shall be held in rotation at the offices
          of CellStar and PBMS.
     d.   If the matter has not been resolved within thirty (30) days of the
          meeting of the senior executives (which period may be extended by
          mutual agreement), the parties will attempt in good faith to resolve
          the controversy or claim under the commercial Mediation Rules of the
          American Arbitration Association, before resorting to arbitration,
          litigation, or some other dispute resolution procedure.
     e.   If the parties cannot resolve the dispute by mediation, the
          controversy or claim arising out of or relating to this Agreement,
          shall be settled by binding arbitration in accordance with the
          Commercial Arbitration Rules of the American Arbitration Association.
          The decision of the Arbitrator(s) is/are considered self-execution and
          failure of either party to abide by the decision may be considered to
          be a breach of contract.   Judgment upon the award rendered by the
          arbitrator(s) may also be entered in any court having jurisdiction
          thereof.  for the 

                                       29
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

          purpose of determining federal diversity jurisdiction the parties are
          considered residents and domicilliaries of different states.
     f.   Nothing in this provision shall prevent the parties from mutually
          agreeing to use an alternative means to resolve the dispute, such as a
          "mini-trial" or other procedure, whether or not it is sponsored by the
          American Arbitration Association.  Additionally, nothing in this
          Section 49 shall restrict either party from seeking injunctive relief
          under Section 16.c. of this Agreement and with respect to CellStar's
          obligation to sell Dedicated Products only to PBMS' Customer, unless
          otherwise permitted by PBMS.

50.  PRECEDENCE

     In the event of any conflict or inconsistency contained within this
     Agreement and for purposes of resolving disputes between the parties
     regarding the interpretation of this Agreement, resolution thereof shall be
     made by giving precedence to the following portions of this Agreement in
     the order listed:

     1.  Exhibits
     2.  Main Body
     3.  Orders
     4.  Procedures Manual (Appendix 1)

     Notwithstanding the above, if PBMS includes any specific payment or
     delivery instructions in the applicable Order which conflict with the
     Exhibits, Main Body, or Procedures Manual, those instructions shall take
     precedence over the Exhibits, Main Body and Procedures Manual but only with
     respect to those specific instructions.

51.  LIMITATION OF LIABILITY

     In no event will either party be liable to the other under this Agreement
     for any indirect, special, or consequential damages, such as frustration of
     economic or business expectations, or lost profits or revenues, whether or
     not the other party has been informed of the possibility of such damages.
     [REDACTED] Nothing in this Section 51 shall limit either party's liability
     in connection with payments or credits which are due or thereafter due and
     owing from one party to the other or for any payment or credits due or
     thereafter due and owing any product supplier in connection with Products
     ordered from that product supplier.

52.  CORPORATE AUTHORIZATION

     The parties shall take any and all steps necessary or appropriate,
     including without limitation, the taking of appropriate corporate action,
     to implement and to give effect to the provisions of this Agreement. Each
     party acknowledges and agrees that the other has entered into this
     Agreement in reliance of the foregoing. Accordingly, each party agrees that
     the other party may enforce this provision by obtaining specific
     performance or injunctive relief. CellStar, Ltd. is a subsidiary of
     CellStar Corporation which guarantees all

                                       30
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement



__________
"[REDACTED]" indicates confidential portions omitted and filed separately with
the Commission.

<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

     of the obligations of and performance of CellStar, Ltd. under this
     Agreement. By signing this Agreement as a duly authorized officer of
     CellStar Corporation the undersigned waives individual notice to CellStar
     Corporation and commits to indemnify and hold PBMS harmless from any and
     all financial or performance obligations of CellStar, Ltd. which are not
     carried out fully in accordance with the terms of this Agreement.

53.  ENTIRE AGREEMENT

     This Agreement, including all Orders, exhibits and subordinate documents
     attached to or referenced in this Agreement or any Orders and all
     proposals, descriptions, drawings, Specifications, marketing materials and
     other literature published by CellStar in connection with or in
     contemplation of any Order or of this Agreement shall constitute the entire
     agreement between PBMS and CellStar with respect to the subject matter.

                            (Signature Page Follows)

                                       31
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163


IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed
by their respective duly authorized representatives.


PACIFIC BELL MOBILE SERVICES

By:      /s/ KEN ELMER
    ----------------------------------
     (Signature)        
                        
Print Name:  Ken Elmer
            --------------------------
                        
Title: Chief Financial Officer
       -------------------------------
                        
Date Signed:  10/5/96
             -------------------------


CELLSTAR, LTD.
By National Auto Center, Inc., its General Partner

By:      /s/ R.M. GOZIA
    ----------------------------------
     (Signature)        
                        
Print Name:  Richard M. Gozia
            --------------------------
                        
Title: Executive Vice President
       -------------------------------
                        
Date Signed:  10/7/96
             -------------------------


BY SIGNING THIS AGREEMENT, CELLSTAR CORPORATION FULLY ACCEPTS AND GUARANTEES THE
PERFORMANCE AND FINANCIAL OBLIGATIONS OF CELLSTAR, LTD.

CELLSTAR CORPORATION                    CELLSTAR CORPORATION
                              
By:  /s/ R.M. GOZIA                     By:  /s/ ELAINE F. RODRIGUEZ
    ---------------------------------       ----------------------------------
     (Signature)                             (Signature)                      
                                                                              
Print Name: Richard M. Gozia            Print Name: Elaine Flud Rodriguez
            -------------------------               --------------------------
                                                                              
Title: Executive Vice President         Title: Vice President                 
       ------------------------------          -------------------------------
                                                                              
Date Signed: 10/7/96                    Date Signed: 10/7/96
             ------------------------                ------------------------- 

                         PROPRIETARY AND CONFIDENTIAL

                                       32
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                   EXHIBIT A
                  EXECUTIVE ORDERS AND ASSOCIATED REGULATIONS

PBMS as a common carrier of telecommunications services, engage in work as
contractors for various departments and agencies of the United States
Government.  Also, certain facilities may be constructed pursuant to federally
assisted construction programs.  Because of the foregoing, work under this
contract may be subject to the provisions of certain Executive Orders, federal
laws and associated regulations.  To the extent that such Executive Orders,
federal laws and associated regulations apply to the work under this contract,
and only to that extent, Contractor agrees to comply with the provisions of all
such Executive Orders, federal laws and associated regulations, as now in force
or as may be amended in the future, including, but not limited to the following:

1. EQUAL EMPLOYMENT OPPORTUNITY PROVISIONS

   In accordance with Executive Order 11246, dated September 24, 1965, and 41
   C.F.R.(S)60-1.4, the parties incorporate herein by this reference the
   regulations and contract clauses required by those provisions to be made a
   part of nonexempt contracts and subcontracts.

2. CERTIFICATION OF NON SEGREGATED FACILITIES

   In accordance with Executive order 11246, dated September 24, 1965, and 41
   C.F.R.(S)60-1.8, Contractor certifies that is does not and will not maintain
   or provide for its employees any facilities segregated on the basis of race,
   color, religion, sex, or national origin at any of its establishments, and
   that it does and will not permit its employees to perform their services at
   any location, under its control, where such segregated facilities are
   maintained. The term "facilities" as used herein means waiting rooms, work
   areas, restaurants and other eating areas, time clocks, restrooms, wash
   rooms, locker rooms and other storage or dressing areas, parking lots,
   drinking fountains, recreation or entertainment areas, transportation and
   housing facilities provided for employees, provided that separate or single-
   user toilet and necessary changing facilities shall be provided to assure
   privacy between the sexes. Contractor will obtain similar certifications from
   proposed subcontractors prior to the award of any nonexempt subcontract.

3. CERTIFICATION OF AFFIRMATIVE ACTION PROGRAM

   Contractor certifies that it has developed and is maintaining an Affirmative
   Action Plan as required by 41 C.F.R.(S)60-1.40.

4. CERTIFICATION OF FILING

   Contractor certifies that it will file annually, on or before the 31st day of
   March, complete and accurate reports on Standard Form 100 (EEO-1) or such
   forms as may be promulgated in its place as required by 41 C.F.R.(S)60-1.7.

5. AFFIRMATIVE ACTION FOR DISABLED VETERANS AND VETERANS OF THE VIETNAM ERA

   In accordance with Executive Order 11701, dated January 15, 1974, and 41
   C.F.R.(S)60-250.20, the parties incorporate herein by this reference the
   regulations and contract clauses required by those provisions to be made a
   part of Government contracts and subcontracts.

6. AFFIRMATIVE ACTION FOR HANDICAPPED PERSONS

   In accordance with Executive Order 11758, dated January 15, 1974, and 41
   C.F.R.(S)60-741.20, the parties incorporate herein by this reference the
   regulations and contract clauses required by those provisions to be made a
   part of Government contracts and subcontracts.

7. UTILIZATION OF SMALL BUSINESS CONCERNS AND SMALL DISADVANTAGED BUSINESS
   CONCERNS

   48 C.F.R., Ch. 1, (S)19.704(4) and 19.708(a) require that the following
   clause is included:
   Utilization of Small Business Concerns and Small Disadvantaged Business
   Concerns (June, 1985)

   (a) It is the policy of the United States that small business concerns and
       small business concerns owned and controlled by socially and economically
       disadvantaged individuals shall have the maximum practicable opportunity
       to participate in performing contracts let by any Federal agency,
       including contracts and subcontracts for subsystems, assemblies,
       components, and related services for major systems. It is further the
       policy of the United States that its prime contractors establish
       procedures to ensure the timely payment of amounts due pursuant to the
       terms of their subcontracts with small business concerns and small
       business concerns owned and controlled by socially and economically
       disadvantaged individuals.

   (b) The Contractor hereby agrees to carry out this policy in the awarding of
       subcontracts to the fullest extent consistent with efficient contract
       performance. The Contractor further agrees to cooperate in any studies or
       surveys as may be conducted by the United States Small Business
       Administration or the awarding agency of the United States as may be
       necessary to determine the extent of the Contractor's compliance with
       this clause.

   (c) As used in this contract, the term "small business concern" shall mean a
       small business as defined pursuant to section 3 of the Small Business Act
       and relevant regulations promulgated pursuant thereto. The term "small
       business concern owned and controlled by socially and economically
       disadvantaged individuals" shall mean a small business concern:

       (1) Which is at least 51 percent owned by one or more socially and
           economically disadvantaged individuals; or, in the case or any
           publicly owned business, at least 51 percent of the stock of which is
           owned by one or more socially and economically disadvantaged
           individuals; and

       (2) Whose management and daily business operations are controlled by one
           or more of such individuals.

   The Contractor shall presume that socially and economically disadvantaged
   individuals include Black Americans, Hispanic Americans, Native Americans,
   Asian-Pacific Americans, Asian-Indian Americans and other minorities, or any
   other individual found to be disadvantaged by the Administration pursuant to
   section 8(a) of the Small Business Act.

                                       1
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                   CELLSTAR and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
   (d) Contractors acting in good faith may rely on written representations by
       their subcontractors regarding their status as either a small business
       concern or a small business concern owned and controlled by socially and
       economically disadvantaged individuals.

   Small Business and Small Disadvantaged Business Subcontracting Plan

   Contractor, unless it is a small business concern, as defined in section 3 of
   the Small Business Act, agrees to adopt and comply with a small business and
   small disadvantaged business subcontracting plan, which shall be included in
   and made a part of this contract. The parties incorporate herein by this
   reference the regulations and contract clauses required by 48 C.F.R., Ch. 1,
   (S)19-704(4) and 19.708(b) to be made a part of Government contracts and
   subcontracts.

8. WOMEN-OWNED SMALL BUSINESSES

   As prescribed in 48 C.F.R., Ch. 1, (S)19.902, the following clause is
   included in solicitations and contracts when the contract amount is expected
   to be over the small purchase threshold, unless (a) the contract is to be
   performed entirely outside the United States, its possessions, Puerto Rico,
   and the Trust Territory of the Pacific Islands, or (b) a personal services
   contract is contemplated:

   (a) "Women-owned small businesses", as used in this clause, means businesses
       that are at least 51 percent owned by women who are United States
       Citizens and who also control and operate the business.

       "Control", as used in this clause, means exercising the power to make
       policy decisions.

       "Operate", as used in this clause, means being actively involved in the
       day-to-day management of the business

   (b) It is the policy of the United States that women-owned small businesses
       shall have the maximum practicable opportunity to participate in
       performing contracts awarded by any Federal agency.

   (c) The Contractor agrees to use its best efforts to give women-owned small
       businesses the maximum practicable opportunity to participate in the
       subcontracts it awards to the fullest extent consistent with the
       efficient performance of its contract.

9. LABOR SURPLUS AREA CONCERNS

   As prescribed in 48 C.F.R., Ch. 1, (S)20.302(a)(b), the following clauses are
   included:

   (a) Applicability. This clause is applicable if this contract exceeds the
       appropriate small purchase limitation in Part 13 of the Federal
       Acquisition Regulation.

   (b) Policy. It is the policy of the Government to award contracts to concerns
       that agree to perform substantially in labor surplus areas (LSA's) when
       this can be done consistent with the efficient performance of the
       contract and at prices no higher than are obtainable elsewhere. The
       Contractor agrees to use its best efforts to place subcontracts in
       accordance with this policy.

   (c) Order of Preference. In complying with paragraph (b) above and with
       paragraph (c) of the clause of this contract entitled Utilization of
       Small Business Concerns and Small Disadvantaged Business Concerns, the
       Contractor shall observe the following order of preference in awarding
       subcontracts: (1) small business concerns that are LSA concerns, (2)
       other small business concerns, and (3) other LSA concerns.

   (d) Definitions. "Labor Surplus Area", as used in this clause, means a
       geographical area identified by the Department of Labor in accordance
       with 20 C.F.R.(S)654, Subpart A, as an area of concentrated unemployment
       or underemployment or an area of labor surplus.

   "Labor surplus area concern", as used in this clause, means a concern that
   together with its first-tier subcontractors will perform substantially in
   labor surplus areas. Performance is substantially in labor surplus areas if
   the costs incurred under the contract on account of manufacturing,
   production, or performance of appropriate services in labor surplus areas
   exceed 50 percent of the contract price.

   Labor Surplus Area Subcontracting Program

   (a) See the Utilization of Labor Surplus Area Concerns clause of this
       contract for applicable definitions.

   (b) The Contractor agrees to establish and conduct a program to encourage
       labor surplus area (LSA) concerns to compete for subcontracts within
       their capabilities when the subcontracts are consistent with the
       efficient performance of the contract at prices no higher than obtainable
       elsewhere. The Contractor shall:

       (1) Designate a liaison officer who will (I) maintain liaison with
           authorized representatives of the Government on LSA matters, (ii)
           supervise compliance with the Utilization of Labor Surplus Area
           Concerns clause, and (iii) administer the Contractor's labor surplus
           are subcontracting program;

       (2) Provide adequate and timely consideration of the potentialities of
           LSA concerns in all make-or-buy decisions;

       (3) Ensure that LSA concerns have an equitable opportunity to compete for
           subcontracts, particularly by arranging solicitations, time for the
           preparation of offers, quantities, specifications and delivery
           schedules so as to facilitate the participation of LSA concerns;

       (4) Include the Utilization of Labor Surplus Area Concerns clause in
           subcontracts that offer substantial LSA subcontracting opportunities;
           and

       (5) Maintain records showing (I) the procedures adopted and (ii) the
           Contractor's performance, to comply with this clause. The records
           will be kept available for review by the Government until the
           expiration of 1 year after the award of this contract, or for such
           longer period as may be required by any other clause of this
           contract, or by applicable law or regulations.

   (c) The Contractor further agrees to insert in any related subcontract that
       may exceed $500,000 and that contains the Utilization of Labor Surplus
       Area Concerns clause, terms that conform substantially to the language of
       this clause, including this paragraph (c), and to notify the Contracting
       Officer of the names of subcontractors.

                                       2
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                   CELLSTAR and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                  EXHIBIT A-1
         PRIME CONTRACTOR MBE/WBE/DVBE JOB SPECIFIC SUBCONTRACTING PLAN
 
Prime Contractor Name:
                      ----------------------------------------------------------
 
Address:
       -------------------------------------------------------------------------
 
Telephone Number:
                 ---------------------------------------------------------------
 
Description Of Goods Or Services:
 
--------------------------------------------------------------------------------
 
--------------------------------------------------------------------------------
 
The following, together with any attachments is submitted as an MBE/WBE/DVBE
subcontracting plan.
 
1. Do you plan to subcontract any portion of the goods or services being quoted,
   bid or proposed?

                        YES                  NO
                           --------            --------
 
2. If answer to item 1 is Yes,
   A. What is your overall company MBE/WBE/DVBE program goal?

     *Minority Business Enterprises (MBEs)                      %
                                                        --------
     *Women Business Enterprises (WBEs)                         %
                                                        --------
     *Disabled Veteran Business Enterprises (DVBEs)             %
                                                        --------
 
 
  B. What is your projected MBE/WBE/DVBE purchases?
 
     *Minority Business Enterprises (MBEs)                      %
                                                        --------
     *Women Business Enterprises (WBEs)                         %
                                                        --------
     *Disabled Veteran Business Enterprises (DVBEs)             %
                                                        --------
 
 
 *SEE MBE/WBE/DVBE SUBCONTRACTING PLAN CLAUSE IN AGREEMENT FOR DEFINITION OF
  MBE, WBE AND DVBE

                                       3
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                   CELLSTAR and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
3. If answer to item 1 is No, or if no MBE/WBE/DVBE subcontractors will be
   utilized where subcontracting has been identified, please explain in detail
   (attach additional sheets if necessary):

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

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

4. List the principal goods and/or services to be subcontracted to
   MBE/WBE/DVBEs, should your quotation, bid or proposal be accepted (attach
   additional sheets if necessary):

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

   -----------------------------------------------------------------------------
 
5. Describe what good faith efforts you plan to undertake to ensure that
   MBE/WBE/DVBEs will have an equitable opportunity to compete for subcontracts
   to be awarded (attach additional sheets if necessary):

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

   -----------------------------------------------------------------------------
 
6. Contractor agrees that it will maintain, if awarded the resulting
   contract/purchase or work order, all necessary documents and records to
   support its efforts to achieve its estimated MBE/WBE/DVBE subcontracting
   goal(s).  Contractor also agrees that it will be responsible for identifying,
   soliciting and qualifying MBE/WBE/DVBE subcontractors.

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

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

7. The following individual, acting in the capacity of MBE/WBE/DVBE coordinator
   for contractor, will:
   *administer the MBE/WBE/DVBE subcontracting plan and
   *cooperate in any studies or surveys as may be required by PBMS in order to
    determine the extent of compliance by contractor with the subcontracting
    plan.
 
    NAME:
         ------------------------------------------------------
    TITLE:                                                     
          -----------------------------------------------------
    TELEPHONE NUMBER:                                          
                     ------------------------------------------
    AUTHORIZED SIGNATURE:                                      
                         --------------------------------------
    DATE:                                                      
         ---------------------------
 
                                       4
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                   CELLSTAR and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-2                                     MASTER AGREEMENT NO. P/PS-960163

                         PACIFIC BELL MOBILE SERVICES
                  MBE/WBE/DVBE SUMMARY SUBCONTRACTING REPORT
                            (Job Specific Results)

1. Reporting Corporation | 2. Contract/Purchase or | 3. This report reflects the
   or Company (Name,     |    Work Order Number    |    utilization of Minority 
   address, city, zip    |                         |    Business Enterprise/
   and telephone number) |                         |    Women Business Enter-
                         |                         |    prise/Disabled Veterans
                         |                         |    Enterprise (MBE/WBE/
                         |                         |    DVBE) subcontractors 
                         |                         |    for period
                         |                         |  
                         |                         |    ________________ through
                         |                         |  
                         |                         |    ________________________
                         |                         |    (Please indicate dates)
                                                        
4.                      SUBCONTRACT DOLLAR AND PERCENTAGE

Ethnicity                           Actual             Cumulative        
                                      for                                
                                    Period                               
                                                                         
                                   $   |  %            $   |   %          
Polynesian Female                      |                   |              
Polynesian Male                        |                   |              
Filipino Female                        |                   |              
Filipino Male                          |                   |              
Hispanic Female                        |                   |              
Hispanic Male                          |                   |              
Black Female                           |                   |              
Black Male                             |                   |              
Asian Female                           |                   |
Asian Male                             |                   |
Native American Female                 |                   |
Native American Male                   |                   |
Multi-Ethnic Female                    |                   |
Multi-Ethnic Male                      |                   |
Non-Minority Female                    |                   |
Disabled Veteran                       |                   |

*See Attached Definitions    Percent of MBE/WBE/DVBE Purchase/Total Purchase
 
                                       5
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-2                                     MASTER AGREEMENT NO. P/PS-960163
 
5.                            SUBCONTRACT ACHIEVEMENT
<TABLE> 
<CAPTION> 
                            Subcontracting Plan Estimate       Actual for Period          Cumulative
                               MBE      WBE      DVBE        MBE     WBE     DVBE        MBE      WBE     DVBE
<S>                           <C>      <C>      <C>         <C>     <C>     <C>         <C>      <C>      <C> 
Subcontracted Dollars          $       $        $           $       $       $           $        $        $
                               -----   -----    -----       -----   -----   -----       -----    -----    -----
Total Contract/Purchase or                                                                  
 Work Order Dollars                                         $                           $
                                                            ---------------------       -----------------------
Subcontracted Percent to                                                                    
 Total Dollars                 %       %        %           %       %        %          %        %        %
                               -----   -----    -----       -----   -----   -----       -----    -----    -----
</TABLE>

                                       6
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
               CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-2                                     MASTER AGREEMENT NO. P/PS-960163

6. MBE/WBE/DVBE Subcontractor(s) (Name, address, city, zip, telephone number),
   description of goods or service(s) supplied during this reporting and total
   dollars paid.  (Attach additional sheets if necessary)
 
Name_____________________ | _________________________ | _______________________
Address__________________ | _________________________ | _______________________
City, State, Zip_________ | _________________________ | _______________________
Telephone 
Number___________________ | _________________________ | _______________________
Goods/Service(s)_________ | _________________________ | _______________________
Ethnicity________________ | _________________________ | _______________________
Total Dollars____________ | _________________________ | _______________________
 
7. Remarks (Explain if the actual results as identified in items 4 and 5 are
   below estimated MBE/WBE/DVBE utilization goal submitted as part of this
   contract/purchase or work order).

------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
8. MBE/WBE/DVBE         |    I hereby certify that      |         Date
   Coordinator          |    the above information      |
   (Name & Title)       |    is true and correct        |
   (Print or Type)      |                               |
                        |                               |
_______________________ |                               | 
_______________________ | _____________________________ | ____________________ 
                        |         Signature             |
________________________|_______________________________|_____________________ 
                        |                               |
9. Approving Officer    |    I hereby certify that      |         Date
   (Name & Title)       |    the above information      |
   (Print or Type)      |    is true and correct        |
_______________________ |                               | 
 
                                       7
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-2                                     MASTER AGREEMENT NO. P/PS-960163

_______________________ |                               | 
_______________________ | _____________________________ | ____________________ 
                        |         (Signature)           |
________________________|_______________________________|_____________________ 
10. This summary report should be mailed
    promptly to:
    Pacific Bell Mobile Services            Note: Questions and/or
    MBE/WBE/DVBE Operations Staff                 requests for assistance
    Results and Analysis Administrator            may be referenced to the
    2600 Camino Ramon, Room 1E400                 MBE/WBE/DVBE
    San Ramon, California 94583                   Subcontracting Administrator 
                                                  at (510) 823-7048
 
                                       8
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

                                  EXHIBIT A-3
      PRIME CONTRACTOR MBE/WBE/DVBE COMMODITY PRODUCT SUBCONTRACTING PLAN
 
Prime Contractor Name:
                      ----------------------------------------------------------
 
Address:
        ------------------------------------------------------------------------
 
Telephone Number:
                 ---------------------------------------------------------------
 
RFQ/RFB/RFP/RFI Number (if 
  applicable)
             -------------------------------------------------------------------
 
Description Of Goods Or Services:
 
--------------------------------------------------------------------------------

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

Definition:  A commodity (or commercial) product is defined as a unit in regular
----------                                                                      
production that is sold in substantial quantities to the general public and/or
industry at regular prices.

If a company is offering a commodity product, then the subcontracting plan may
relate to the company's general production of both commercial and noncommercial
products, rather than just specific items being procured under the contract.

The following, together with any attachments is submitted as an MBE/WBE/DVBE
subcontracting plan.
 
1. Do you plan to subcontract any portion of the goods or services being quoted,
   bid or proposed?

                      YES                     NO
                         --------------         ---------------

2. If answer to item 1 is Yes,
   A.  What is your overall company MBE/WBE/DVBE program goal?
 
   *Minority Business Enterprises (MBEs)                        %
                                                        --------
   *Women Business Enterprises (WBEs)                           %
                                                        --------
   *Disabled Veteran Business Enterprises (DVBEs)               %
                                                        --------
 
B. What is your projected MBE/WBE/DVBE purchases?
 
   *Minority Business Enterprises (MBEs)                        %
                                                        --------
   *Women Business Enterprises (WBEs)                           %
                                                        --------
   *Disabled Veteran Business Enterprises (DVBEs)               %
                                                        --------
 
*SEE MBE/WBE/DVBE SUBCONTRACTING PLAN CLAUSE IN AGREEMENT FOR DEFINITION OF MBE,
 WBE AND DVBE

                                       9
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>

                                                MASTER AGREEMENT NO. P/PS-960163

3. If answer to item 1 is No, or if no MBE/WBE/DVBE subcontractors will be
   utilized where subcontracting has been identified, please explain in detail
   (attach additional sheets if necessary):

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

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

4. List the principal goods and/or services to be subcontracted to
   MBE/WBE/DVBEs, should your quotation, bid or proposal be accepted (attach
   additional sheets if necessary):
 
   -----------------------------------------------------------------------------

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

5. Describe what good faith efforts you plan to undertake to ensure that
   MBE/WBE/DVBEs will have an equitable opportunity to compete for subcontracts
   to be awarded (attach additional sheets if necessary):

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

   -----------------------------------------------------------------------------
 
6. Contractor agrees that is will maintain, if awarded the resulting
   contract/purchase or work order, all necessary documents and records to
   support its efforts to achieve its estimated MBE/WBE/DVBE subcontracting
   goal(s). Contractor also agrees that it will be responsible for identifying,
   soliciting and qualifying MBE/WBE/DVBE subcontractors.

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

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

7. The following individual, acting in the capacity of MBE/WBE/DVBE coordinator
   for contractor, will:

   *administer the MBE/WBE/DVBE subcontracting plan
   *submit summary reports (in the form Exhibit A-4), and
   *cooperate in any studies or surveys as may be required by PBMS in order to
    determine the extent of compliance by contractor with the subcontracting
    plan.
 
 
    NAME:
         ------------------------------------------------------
    TITLE:                                                     
          -----------------------------------------------------
    TELEPHONE NUMBER:                                          
                     ------------------------------------------
    AUTHORIZED SIGNATURE:                                      
                         --------------------------------------
    TYPED/PRINTED NAME:
                       ----------------------------------------
    TITLE:                  DATE:
          ------------------     ------------------------------
 
                                      10
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-4                                     MASTER AGREEMENT NO. P/PS-960163

                         PACIFIC BELL MOBILE SERVICES
                  MBE/WBE/DVBE SUMMARY SUBCONTRACTING REPORT
                            (Commodity Results)

1. Reporting Corporation | 2. Contract/Purchase or | 3. This report reflects the
   or Company (Name,     |    Work Order Number    |    utilization of Minority 
   address, city, zip    |                         |    Business Enterprise/
   and telephone number) |                         |    Women Business Enter-
                         |                         |    prise/Disabled Veterans
                         |                         |    Enterprise (MBE/WBE/
                         |                         |    DVBE) subcontractors 
                         |                         |    for period
                         |                         |  
                         |                         |    ________________ through
                         |                         |  
                         |                         |    ________________________
                         |                         |    (Please indicate dates)
                                                        
4.                      SUBCONTRACT DOLLAR AND PERCENTAGE
<TABLE>
<CAPTION>
Ethnicity              Actual             Cumulative        Ethnicity               Actual             Cumulative 
                         for                                                          for                         
                       Period                                                       Period                        
<S>                   <C>                 <C>               <C>                      <C>                 <C>
                      $   |  %            $   |   %                                  $   |  %            $   |   %  
Polynesian Female         |                   |              Asian Female                |                   |      
Polynesian Male           |                   |              Asian Male                  |                   |      
Filipino Female           |                   |              Native American Female      |                   |      
Filipino Male             |                   |              Native American Male        |                   |      
Hispanic Female           |                   |              Multi-Ethnic Female         |                   |      
Hispanic Male             |                   |              Multi-Ethnic Male           |                   |      
Black Female              |                   |              Non-Minority Female         |                   |      
Black Male                |                   |              Disabled Veteran            |                   |      
</TABLE>
*See Attached Definitions    Percent of MBE/WBE/DVBE Purchase/Total Purchase
 
                                      11
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-4                                     MASTER AGREEMENT NO. P/PS-960163
 
5.                            SUBCONTRACT ACHIEVEMENT
<TABLE> 
<CAPTION> 
                            Subcontracting Plan Estimate       Actual for Period          Cumulative
                               MBE      WBE      DVBE        MBE     WBE     DVBE        MBE      WBE     DVBE
<S>                           <C>      <C>      <C>         <C>     <C>     <C>         <C>      <C>      <C> 
MBE/WBE/DVBE Purchases to
Sales                          %       %        %           %       %        %          %        %        %
                               -----   -----    -----       -----   -----   -----       -----    -----    -----
</TABLE>

                                      12
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
               CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-4                                     MASTER AGREEMENT NO. P/PS-960163

6. MBE/WBE/DVBE Subcontractor(s) (Name, address, city, zip, telephone number),
   description of goods or service(s) supplied during this reporting and total
   dollars paid.  (Attach additional sheets if necessary)
 
Name_____________________ | _________________________ | _______________________
Address__________________ | _________________________ | _______________________
City, State, Zip_________ | _________________________ | _______________________
Telephone 
Number___________________ | _________________________ | _______________________
Goods/Service(s)_________ | _________________________ | _______________________
Ethnicity________________ | _________________________ | _______________________
Total Dollars____________ | _________________________ | _______________________
 
7. Remarks (Explain if the actual results as identified in items 4 and 5 are
   below estimated MBE/WBE/DVBE utilization goal submitted as part of this
   contract/purchase or work order).

------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
------------------------------------------------------------------------------- 
8. MBE/WBE/DVBE         |    I hereby certify that      |         Date
   Coordinator          |    the above information      |
   (Name & Title)       |    is true and correct        |
   (Print or Type)      |                               |
                        |                               |
_______________________ |                               | 
_______________________ | _____________________________ | ____________________ 
                        |         Signature             |
________________________|_______________________________|_____________________ 
                        |                               |
9. Approving Officer    |    I hereby certify that      |         Date
   (Name & Title)       |    the above information      |
   (Print or Type)      |    is true and correct        |
_______________________ |                               | 
 
                                      13
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
Exhibit A-4                                     MASTER AGREEMENT NO. P/PS-960163

_______________________ |                               | 
_______________________ | _____________________________ | ____________________ 
                        |         (Signature)           |
________________________|_______________________________|_____________________ 
10. This summary report should be mailed
    promptly to:
    Pacific Bell Mobile Services            Note: Questions and/or
    MBE/WBE/DVBE Operations Staff                 requests for assistance
    Results and Analysis Administrator            may be referenced to the
    2600 Camino Ramon, Room 1E400                 MBE/WBE/DVBE
    San Ramon, California 94583                   Subcontracting Administrator 
                                                  at (510) 823-7048
 
                                      14
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

                                                                       EXHIBIT B

                                   CELLSTAR
                     DESCRIPTION OF PRODUCTS AND SERVICES

<TABLE>
<CAPTION>
--------------------------------------------------------------------------------
       DESCRIPTION                          ONE TIME   MONTHLY      PRICE 
                                               FEE       FEE       [REDACTED]
--------------------------------------------------------------------------------
<S>                                         <C>        <C>      <C>
1      LOGISTICS
--------------------------------------------------------------------------------
A   Hardware Costs                           [REDACTED]
--------------------------------------------------------------------------------
B   Personnel Costs                          [REDACTED]
--------------------------------------------------------------------------------
C   Assembly Costs                           [REDACTED]        [REDACTED]   
--------------------------------------------------------------------------------
D   Advance Return and Pick to Ship                            [REDACTED]
--------------------------------------------------------------------------------
E   Fulfillment Costs                                          [REDACTED]
                                                                
--------------------------------------------------------------------------------
F   Returns Processing *                          
    . Receiving and Sort                                       [REDACTED]
    . Triage and return to vendor                               
    . Triage and repair/refurb                                  
                                                                
    . Restocking Fee                                            
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
2      INVENTORY CARRYING COSTS
--------------------------------------------------------------------------------
    A recurring charge, calculated                     [REDACTED]
    and billed monthly as a "cost                        
    of capital" charged on [REDACTED]
    







--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
3     CREDIT AND COLLECTIONS
--------------------------------------------------------------------------------
  A Receivable Maintenance                             [REDACTED]
    Costs  (calculated on                              
    [REDACTED]








--------------------------------------------------------------------------------
  B Skid Storage Fee (after [REDACTED] days)                    [REDACTED]
--------------------------------------------------------------------------------
  C Credit and Collection Services                     [REDACTED]
--------------------------------------------------------------------------------
</TABLE> 
*    In addition, PBMS will be billed for the difference when A stock is written
     down and for return freight of non PBMS items

1




__________
"[REDACTED]" indicates confidential portions omitted and filed separately with
the Commission.

<PAGE>
 
                                                MASTER AGREEMENT NO. P/PS-960163

                                   EXHIBIT C



                        PBMS Credit & Collection Costs
<TABLE>
<CAPTION>
--------------------------------------------------------------
       Item            Annual   Monthly         Comment
--------------------------------------------------------------
<S>                  <C>       <C>        <C>
Collection Analyst    [REDACTED] [REDACTED] [REDACTED]
A/R Posting Rep       
Lock Box              
PBMS DID Line         
Long Distance         
D&B Investigation     
Postage               
Invoices              
Credit Applications   
EDI Transactions      
AS 400                
Business Analyst      
Sr. Programmer        
Programmer            
EDI Specialist        
EBE @ 20%             
--------------------------------------------------------------
     Sub-Total       
--------------------------------------------------------------
Contingency          
--------------------------------------------------------------
       TOTAL         
--------------------------------------------------------------
      Margin         
--------------------------------------------------------------
    Grand Total      
--------------------------------------------------------------
</TABLE>




__________
"[REDACTED]" indicates confidential portions omitted and filed separately with
the Commission.

<PAGE>
 
EXHIBIT D                                       MASTER AGREEMENT NO. P/PS-960163


                          PACIFIC BELL PCS PRICE LIST

OEM ACCESSORIES FOR MOTOROLA FLARE
 
BATTERIES
--------------------------------------------------------------------------------
SNN4512PB                          TALK PACK NICD BATTERY - BLACK    [REDACTED] 
  
SNN4516PB                          TALK PACK NIMH BATTERY - BLACK         
SNN4582PB                          XT TALK PACK NICD BATTERY - BLACK      
SNN4585PB                          XT TALK PACK NIMH BATTERY - BLACK      
SNN4588PB                          STANDARD NICD BATTERY - BLACK          
SNN4591PB                          STANDARD NIMH BATTERY - BLACK          
SNN4594PB                          XT SLIM NICD BATTERY - BLACK           
SNN4597PB                          XT SLIM NIMH BATTERY - BLACK           
 
POWER PLUS TALK AND CHARGE
--------------------------------------------------------------------------------
SLN9933PB                          ULTRA SAVER/CHARGER                    
 
LEATHER CASE
--------------------------------------------------------------------------------
LCSXPB                             LEATHER CASE                           
 
OEM ACCESSORIES FOR NOKIA 2190
 
BATTERIES
--------------------------------------------------------------------------------
BBH2SPB                            400 MAH NICD SLIM BATTERY              
BBH1SPB                            500 MAH NIMH SLIM BATTERY              
BBH2HPB                            1100 MAH NICD HICAP BATTERY            
BBH1HPB                            1500 MAH NIMH HICAP BATTERY            
 
POWER PLUS TALK AND CHARGE
--------------------------------------------------------------------------------
LCH2PB                             RAPID IN-CAR CHARGER                   
 
LEATHER CASE
--------------------------------------------------------------------------------
LCSXPB                             LEATHER CASE                           
 
OEM ACCESSORIES FOR ERICSSON
 CH337
 
BATTERIES
--------------------------------------------------------------------------------
BKB1931001PB                       550MAH SLIMLINE NIMH BATTERY           
BKB1931009PB                       950 MAH MIDCAP NIMH BATTERY            
BKB1931015PB                       700 MAH BASIC NICD BATTERY         **  
BKB193025PB                        1000 MAH HICAP NICD BATTERY        **  
*BKB1931021PB                      1200 MAH NIMH BATTERY                  
*BKB193085PB                       500 MAH NIMH BATTERY                   
 
POWER PLUS TALK AND CHARGE
--------------------------------------------------------------------------------
BML1631001PB                       VEHICLE POWER ADAPTER PLUS         **  
 
LEATHER CASE
KRY1041032PB                       FLIP LEATHER POUCH                 **  

NOTE:
"*"  REPRESENTS NEW SKU
"**"  REPRESENTS NEW PRICING
"PB"  SUFFIX ON ABOVE PART NUMBERS REPRESENT PACIFIC BELL CUSTOM PACKAGING.



__________
"[REDACTED]" indicates confidential portions omitted and filed separately with
the Commission.

<PAGE>
 
EXHIBIT E                                       MASTER AGREEMENT NO. P/PS-960163

PACIFIC BELL                             ---------------------------------------
MOBILE SERVICES                                       Purchase Order
4410 Rosewood Drive, Suite 400           ---------------------------------------
Pleasanton, CA 94588                      PURCHASE ORDER NO.   REVISION   PAGE
Phone (510) 227-2200                     
Fax   (510) 227-2223
                                         ---------------------------------------
                                          THIS PURCHASE ORDER NO. MUST APPEAR ON
                                          ALL INVOICES, PACKING LISTS, CARTONS
                                          AND CORRESPONDENCE RELATED TO THIS
                                          ORDER.
                                         ---------------------------------------

                                           SHIP TO:


                                         ---------------------------------------
VENDOR:                                    BILL TO:
 

--------------------------------------------------------------------------------
CUSTOMER ACCT. NO.     VENDOR NO.    DATE OF ORDER/BUYER     REVISED DATE/BUYER

--------------------------------------------------------------------------------
PAYMENT TERMS           SHIP VIA                            F.O.B.

--------------------------------------------------------------------------------
FREIGHT TERMS           REQUESTOR/DELIVER TO                CONFIRM TO/TELEPHONE

--------------------------------------------------------------------------------
ITEM PART NUMBER/  DELIVERY DATE   QUANTITY   UNIT   UNIT PRICE   EXTENSION  TAX
     DESCRIPTION
--------------------------------------------------------------------------------
 
 
 
 
 
 










 
--------------------------------------------------------------------------------
 APPROVAL:                                         TOTAL
                                                  ------------------------------
                                                   AUTHORIZATION
 
 
------------------------------ ------------------ ------------------------------
 Requested By                   Phone              Name
 
                                                  ------------------------------
                                                   Signature

------------------------------ ------------------ ------------------------------
 Prepared By                    Phone

                                                  ------------------------------
                                                   Date
--------------------------------------------------------------------------------

                                      45
                         PROPRIETARY AND CONFIDENTIAL
                       Not for Use or Disclosure Outside
                CELLSTAR, LTD. and PACIFIC BELL MOBILE SERVICES
                        Except Under Written Agreement
<PAGE>
 
EXHIBIT F                                       MASTER AGREEMENT NO. P/PS-960163

                              Assembly Cost Model
                                  [REDACTED]





__________
"[REDACTED]" indicates confidential portions omitted and filed separately with
the Commission.