<PAGE>

                                    EX. 10.16

                            STOCK PURCHASE AGREEMENT

        STOCK PURCHASE AGREEMENT made as of the 24th day of December, 1997 by
and between TTR INC., a private company established under the laws of the State
of Delaware (the "Company") with offices at 1841 Broadway, New York, N.Y. and
BISCOUNT OVERSEAS LTD., a private company established under the laws of ________
with offices at _____________________________, Switzerland (the "Purchaser").

                               W I T N E S S E T H

        WHEREAS, the Purchaser desires to subscribe for and purchase 64,000
shares of Common Stock, par value $0.001, of the Company (the "Shares"), for an
aggregate purchase price of $400,000 (the "Purchase Price") and to acquire
warrants ("Warrants") to purchase additional shares of the Company's Common
Stock (the "Common Stock");

        WHEREAS, the Company is willing to sell the Shares and the Warrants to
the Purchaser on the terms and conditions set forth herein.

        NOW, THEREFORE, in consideration of the mutual agreements and
considerations set forth herein, the parties hereby agree as follows.

1.      Subscription for and Purchase of Stock; Issuance of Warrants

        1.1  Purchase of Stock. Subject to the terms and conditions stated
herein, the Purchaser hereby subscribes for and agrees to purchase, and the
Company agrees to sell to the Purchaser, the Shares in consideration of the
payment by the Purchaser of the Purchase Price, in the manner and on each of the
dates set forth below (each such date being a "Purchase Date"):

        (i) on the Initial Closing Date (as defined below in Section 1.4),
        48,000 Shares upon payment of an aggregate Purchase Price of $300,000;
        and

        (ii) on the Second Closing Date (as defined below Section 1.4), 16,000
        Shares upon payment of an aggregate Purchase Price of $100,000.

        1.2  Delivery. The Purchaser shall deliver to the Company, on each of
the Purchase Dates, the full amount of the Purchase Price then payable hereunder
in immediately available funds by wire transfer to a bank account designated by
the Company or by check made payable to Company or as Company designates. Upon
and subject to receipt of the full amount of the Purchase Price then due, the
Company shall deliver to the Purchaser stock certificate(s), registered in the
Purchaser's name for such number of the Shares then purchased.

        1.3  Purchase of Warrants. Contemporaneous with the purchase of the
Shares as provided above, the Purchaser will purchase from the Company, and the









<PAGE>

<PAGE>
                                       2


Company will sell to the Purchaser, warrants to purchase an additional 33,000
shares of Common Stock, for an aggregate purchase warrant purchase price of
$330, on the terms and conditions contained in the Warrant attached hereto as
Exhibit A ("Warrants"). The Warrants will be issued as follows:

        (i) on the Initial Closing Date, Warrants for 25,000 Shares will be
        issued upon payment of $250; and

        (ii) on the Second Closing Date, Warrants for 8,000 Shares will be
        issued upon payment of $80.00

        1.4  Closings. The "Initial Closing Date" shall be the later of (i)
December 20, 1997 and (ii) the date on which the consent referred to in Section
7 shall have been obtained. The Second Closing Date shall be the date which is
30 days after the Initial Closing Date.

2.      Representations of the Purchaser; Restrictions on Transfer

        2.1  General Restriction on Transfer. Except for transfers otherwise
permitted by this Agreement or applicable law, the Purchaser agrees that it will
not transfer any of the Shares, Warrants, Option Shares (as defined in Section
6), the Option Warrants (as defined in Section 6) or the shares of Common Stock
issuable upon the exercise of the Warrants or the Option Warrants (collectively,
the "Securities").

        2.2  Not for Resale. The Purchaser represents that it is acquiring the
Securities for investment for its own account and not with a view to, or for
resale in connection with, the distribution or other disposition thereof. The
Purchaser agrees that it will not, directly or indirectly, offer, transfer,
sell, assign, pledge, hypothecate or otherwise dispose of (each a "Transfer")
any of the Securities unless such Transfer complies with the provisions of this
Agreement and (i) the Transfer is pursuant to an effective registration
statement under the Securities Act of 1933, as amended, and the rules and
regulations in effect thereunder (the "Securities Act"), or (ii) counsel for the
Purchaser shall have furnished the Company with an opinion, reasonably
acceptable to the Company, that no such registration is required because of the
availability of an exemption under the Securities Act.

        2.3  Certain Permitted Transfers. Notwithstanding the general
prohibition on Transfers contained herein and subject to Section 4 (Lock Up),
the Company acknowledges and agrees that any Transfer in a private transaction
which does not include a public distribution is permitted and need not require
an opinion of counsel, provided, that prior to such Transfer, the transferee
shall deliver to the Company a valid written undertaking to be bound by the
terms of this Agreement.

        2.4  Rule 144 Sales. Subject to the provisions of Section 4 (Lock Up),
the Purchaser may sell at any time any of the Securities in a Rule 144
Transaction (as hereinafter defined); provided, that, each such sale shall be
made in compliance with this Section 2.4. If any of the Securities are disposed
of according to Rule 144 ("Rule 144 Transaction") under the Securities Act or
otherwise, the Purchaser shall promptly









<PAGE>

<PAGE>
                                       3


notify the Company of such intended disposition and shall deliver to the Company
at or prior to the time of such disposition such documentation as the Company
may reasonably request in connection with such sale and, in the case of a
disposition pursuant to Rule 144, shall deliver to the Company an executed copy
of any notice on Form 144 required to filed with the Securities and Exchange
Commission.

        2.5  Legend. Each certificate representing the Shares shall bear the
following legend:

        "THE SECURITIES REPRESENTED BY THIS CERTIFICATE OR INSTRUMENT MAY NOT BE
        TRANSFERRED, SOLD, ASSIGNED, PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED
        OF UNLESS SUCH TRANSFER, SALE OR ASSIGNMENT, PLEDGE, HYPOTHECATION OR
        OTHER DISPOSITION COMPLIES WITH THE PROVISIONS OF A STOCK PURCHASE
        AGREEMENT DATED AS OF DECEMBER__, 1997 (A COPY OF WHICH IS ON FILE WITH
        THE SECRETARY OF THE COMPANY)."

        2.6  Qualified Investor The Purchaser hereby represents and warrants to
the Company as follows:

               (a) it has the requisite knowledge and experience in financial
and business matters to be capable of evaluating the merits and risks of this
investment and to make an informed investment decision with respect thereto, and
it or its advisors have received such information requested by them concerning
the Company in order to evaluate the merits or risks of making this investment.
Further, it is acknowledged that the Purchaser or its attorney, accountant or
advisor have had the opportunity to ask questions of, and receive answers from,
the officers of the Company concerning the terms and conditions of this
investment and to obtain information relating to the Company.

               (b) The purchase of the Securities involves risks which it has
evaluated, and is able to bear the economic risk of such purchase including the
total loss of its investment. It has been advised of the current financial
condition of the Company and of the possible adverse effects of such financial
condition on the Company's general business.

3.      Company's Representations and Warranties

        3.1  The Company has all requisite power and authority to issue, sell
and deliver the Securities in accordance with and upon the terms and conditions
set forth in this Agreement, and all corporate action required to be taken by
the Company for the due and proper authorization, issuance and delivery of the
Securities will, upon delivery thereof, have been validly and sufficiently
taken. The Securities, when sold and paid for as contemplated in this Agreement,
will be duly authorized, validly issued, fully paid and non-assessable and,
except as otherwise provided by applicable law, free of all liens, claims and
encumbrances.









<PAGE>

<PAGE>
                                       4


        3.2  The Company has full corporate right, power and authority to enter
into this Agreement and to issue the Securities, and this Agreement and the
Securities have been or will be duly authorized, executed and delivered by the
Company and constitutes or will constitute the valid and binding agreement of
the Company.

4.      Lock Up

        Notwithstanding anything to the contrary contained herein, the Purchaser
undertakes that it will not undertake a Transfer of any of the Securities until
the end of the sixth (6th) month following the initial Purchase Date hereunder.

5.      Registration Rights

        5.1  Within TEN (10) business days following the filing of the Company's
annual report on FORM 10KSB under the Securities and Exchange Act, as amended,
for the period ended December 31, 1996, but in no event later than April 30,
1998, the Company agrees to file a registration statement [ON FORM S-3 OR OTHER
APPROPRIATE FORM] under the Securities Act of 1933, as amended (hereinafter, the
"Registration Statement"), respecting the resale of the Shares, the Option
Shares and the shares issuable upon exercise of the Warrants and the Option
Warrants (hereinafter, the Registrable Securities) and to use reasonable efforts
to cause such registration statement to become effective as soon as practicable
thereafter. The Purchaser, or its counsel, shall assist the Company in
completing the Registration Statement.

        5.2  Notwithstanding anything to the contrary set forth in this
Agreement, the Company's obligations under this Section 5.1 to file the
Registration Statement and to use its reasonable efforts to cause the
Registration Statement to become effective shall be suspended in the event and
during such period as unforeseen circumstances (including, without limitation,
pending negotiations relating to, or the consummation of, a transaction or the
occurrence of any event) which, based upon advice of the Company's counsel,
would require additional disclosure of material information by the Company in
the Registration Statement as to which the Company has a bona fide business
purpose for preserving the confidentiality thereof or which, based upon the
advice of such counsel, renders the Company unable to comply with SEC
requirements. Any such suspension shall continue only for so long as such event
is continuing.

        Following the effectiveness of the Registration Statement, except as may
be permitted under Section 2.4 of this Agreement, the Purchaser will not effect
any sales of the Registrable Securities at any time after it has received notice
from the Company to suspend sales as a result of a stop order or the occurrence
of any suspension event so that the Company may correct or update the
Registration Statement. The Purchaser may recommence effecting sales of the
Registrable Securities as provided above following further notice to such effect
from the Company, which notice shall be given by the Company promptly after the
withdrawal of any stop order or the conclusion of such suspension event.









<PAGE>

<PAGE>
                                       5


6.      Option

        Subject to the terms and conditions set forth herein, the Purchaser
shall be entitled to acquire, on or before June 30, 1998 (such date of exercise
being the "Option Purchase Date"), an additional 10,000 shares of Common Stock
("Option Shares"), for an aggregate purchase price of $62,500 ("Option Purchase
Price"), PROVIDED, THAT, the Purchaser shall give the Company written notice of
its election to purchase the Option Shares as herein provided no later than the
date on which the Registration Statement referred to in Section 5 has been
initially filed. The Purchaser shall deliver to the Company, on the Option
Purchase Date, the full amount of the Option Purchase Price payable hereunder in
immediately available funds by wire transfer to a bank account designated by the
Company or by check made payable to Company or as Company designates. Upon and
subject to receipt of the full amount of the Option Purchase Price then due, the
Company shall deliver to the Purchaser stock certificate(s), registered in the
Purchaser's name for such number of the Shares then purchased.

        Contemporaneous with the purchase of the Option Shares as provided
above, the Purchaser will purchase from the Company, and the Company will sell
to the Purchaser, warrants to purchase an additional 5,000 shares of Common
Stock (the "Option Warrants"), for an aggregate purchase warrant purchase price
of $50, on the terms and conditions contained in the Warrant attached hereto as
Exhibit A.

        The Option Shares and the Option Warrants shall be subject to the terms
and conditions set forth herein.

7.      Conditions Precedent

        The Purchaser acknowledges and understands that the Company and First
Metropolitan Securities Inc., a Delaware corporation ("First Met") entered into
the Underwriting Agreement, dated as of February 10, 1997 (hereinafter, the
"Underwriter Agreement") relating to an initial public offering of Common Stock
of the Company. Under the terms of the Underwriter Agreement, the written
consent of First Met must be obtained in respect of the issuance of the
Securities. Accordingly, the terms of this Agreement shall be subject to such
consent.

8.      Miscellaneous

        8.1  Notices. All notices and other communications provided herein shall
be in writing and shall be deemed to have been duly given if delivered
personally or sent by certified mail, postage prepaid, to a party's designated
address set froth above, if sent by facsimile, to its facsimile number at such
address.

        8.2  Counterparts; Entire Agreement. This Agreement may be executed in
counterparts. This Agreement and the Warrant annexed hereto constitute the
entire agreement between the parties hereto with respect to the subject matter
hereof.









<PAGE>

<PAGE>
                                       6


        8.3  Binding Effect. The provisions of this Agreement shall be binding
upon and shall inure to the benefit of the parties hereto and their respective
heirs, legal representatives, successors and assigns.

        8.4  Amendment. This Agreement may be amended only by a written
instrument signed by the parties hereto which specifically states that it is
amending this Agreement.

        8.5  Applicable Governing Law. This Agreement and the rights and
obligations of the parties hereto shall be governed by and construed and
enforced in accordance with, the laws of the State of New York.

        8.6  Headings. The headings herein are for convenience of reference
only, do not constitute a part of this Agreement, and shall not be deemed
to limit, expand or otherwise affect any of the provisions hereof.

        IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first written above.

                                            TTR INC.

                                            By:_______________
                                                Marc D. Tokayer
                                            President


                                            BISCOUNT OVERSEAS LTD.

                                            By:___________________

                                            Title:

<PAGE>