Exhibit 3.6.1 -   Form of Series B Preferred Stock.

                     See Restrictive Legends on Reverse Side

                            SERIES B PREFERRED STOCK
                                 $.001 PAR VALUE

                             CERTIFICATE FOR SHARES

                            U.S. WIRELESS CORPORATION
                            (A Delaware Corporation)

Number: PB__________                                            Shares:________



     WHEREAS, U.S. Wireless Corporation (the "Company"),  is authorized to issue
an aggregate of One million  (1,000,000)  shares of Preferred  Stock,  par value
$.01 per  share,  which  may be  issued  in  classes  or in  series,  and  whose
respective  rights,  designations and preferences may be designated from time to
time by a Certificate of Designation by the Board of Directors of U.S.  Wireless
Corporation; and

     WHEREAS,   the  Board  of  Directors  of  U.S.  Wireless  Corporation  have
designated  60,000 shares of Preferred Stock as the "Series B Preferred  Stock,"
pursuant to an Certificate of Restated and Amended  Certificate of Incorporation
as filed by the Company and which  Amendment sets forth the rights,  preferences
and limitations of such Series B Preferred Stock.

     NOW,  THEREFORE,  this  certifies  that  ___________________  the  owner of
____________ (_________) Shares of the Series B Preferred Stock of U.S. Wireless
Corporation, which Preferred Shares are fully paid and non-assessable.

     IN WITNESS WHEREOF,  the said Corporation has caused this Certificate to be
signed by its duly  authorized  officers and its  Corporate  Seal to be hereunto
affixed this __th day of __________, 1999.


      -------------------------                   ------------------------------
        David Klarman                               Dr. Oliver Hilsenrath
        Secretary                                   President



                            U.S. WIRELESS CORPORATION
                                      1993
                                    Delaware


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<PAGE>
The following  abbreviation,  when used in the  inscription  on the face of this
certificate,  shall  be  construed  as  though  they  were  written  out in full
according to applicable laws or regulations: <TABLE> <CAPTION>

<S>               <C>                                       <C>
TEN COM-          as tenants in common                      UNIF GIFT ACT -.......Custodian.........
TEN ENT-          as tenants by the entireties                            (Cust.)      (Minor)
JT TEN-           as joint tenants with right of                       under Uniform Gifts to Minors
                  survivorship and not as tenants           Act......................................
                  in common                                                              (State)
</TABLE>

Additional abbreviation may also be used though not in above list.

     For value  received,..............................hereby  sell,  assign and
transfer unto

Please Insert Social Security or Other
  Identifying Number of Assignee : ____________________


     Please print or  typewrite  name and address  including  postal zip code of
assignee


     Shares of the stock represented by the attached Certificate,  and do hereby
irrevocably constitute and appoint

     Attorney to transfer the said Limited Partnership Interests on the books of
the  within-named  Limited  Partnership  with full power of  substitution in the
premises.

     NOTICE:  The signature to this  assignment must correspond with the name as
written  upon  the  face  of  the  Certificate,  in  every  particular,  without
alteration or enlargement, or any change whatever.

Dated:

SIGNATURE

SIGNATURE GUARANTEED


ELECTION TO PURCHASE


     The undersigned  hereby irrevocably elects to exercise the right to convert
shares of Series B Preferred  Stock into shares of Common  Stock,  and  herewith
tenders said shares of Series B Preferred  Stock in accordance  with the issuers
Certificate of Incorporation.  The undersigned  requests that a certificates for
such  securities  be  registered  in the  name  and  address  of and  that  such
Certificate        be       delivered        to        -------------------------
------------------------------------------------------ ----------- whose address
is . ------------------
------------------------------------------------------------

Dated:


     Signature (Signature must conform in all respects to name of holder)




     THE SECURITIES  REPRESENTED BY THIS  CERTIFICATE  HAVE NOT BEEN  REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), AND MAY NOT BE SOLD OR
OTHERWISE  TRANSFERRED  IN THE ABSENCE OF AN  EFFECTIVE  REGISTRATION  STATEMENT
UNDER THE ACT OR AN OPINION OF COUNSEL SATISFACTORY TO THE CORPORATION THAT SUCH
REGISTRATION IS NOT REQUIRED.

     THE SECURITIES  REPRESENTED BY THIS CERTIFICATE ARE FURTHER RESTRICTED FROM
BEING SOLD OR TRANSFERRED PURSUANT TO CERTAIN HOLDBACK RESTRICTIONS SET FORTH IN
A SUBSCRIPTION AGREEMENT BETWEEN THE HOLDER AND THE CORPORATION.


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