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                                                                     EXHIBIT 4.1



COMMON SHARES

COMMON SHARES

TST

THIS CERTIFICATE IS TRANSFERABLE IN
RIDGEFIELD PARK, NJ OR NEW YORK, NY

CUSIP 900423 10 4
SEE REVERSE FOR CERTAIN DEFINITIONS

TURNSTONE SYSTEMS, INC.
INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE

This Certifies that

is the record holder of

FULLY PAID AND NON-ASSESSABLE SHARES OF THE COMMON STOCK, PAR VALUE $.001 PER
SHARE, OF

Turnstone Systems, Inc., transferable only on the books of the Corporation by
the holder hereof in person or by duly authorized Attorney upon surrender of
this Certificate properly endorsed. This Certificate is not valid unless
countersigned and registered by the Transfer Agent and Registrar. In Witness
Whereof, the Corporation has caused this Certificate to be executed and attested
to by the manual or facsimile signatures of its duly authorized officers, under
a facsimile of its corporate seal to be affixed hereto. Dated:

SECRETARY

CHIEF EXECUTIVE OFFICER

COUNTERSIGNED AND REGISTERED:
BankBoston, N.A.
TRANSFER AGENT AND REGISTRAR
BY
AUTHORIZED SIGNATURE

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TURNSTONE SYSTEMS, INC.

Upon request the Corporation will furnish any holder of shares of Common Stock
of the Corporation, without charge, with a full statement of the powers,
designations, preferences, and relative, participating, optional or other
special rights of any class or series of capital stock of the Corporation, and
the qualifications, limitations or restrictions of such preferences and/or
rights.

The following abbreviations, 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:

TEN COM -
TEN ENT -
JT TEN -

as tenants in common
as tenants by the entireties
as joint tenants with right of
survivorship and not as tenants
in common

UNIF GIFT MIN ACT-D......................Custodian......................
                           (Cust)                       (Minor)

under Uniform Gifts to Minors Act...............................................
                                                  (State)

Additional abbreviations may also be used though not in the 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 ZIP CODE OF ASSIGNEE)

Shares

of Common Stock represented by the within Certificate, and do hereby irrevocably
constitute and appoint

Attorney

to transfer the said stock on the books of the within named Corporation with
full power of substitution in the premises.

Dated
In presence of

X
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X
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.


Signature(s) Guaranteed
By

THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS,
STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN
AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE
17Ad-15.