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                                                              EXHIBIT 10.6

                   SECOND AMENDMENT TO LEASE

   THIS SECOND AMENDMENT TO LEASE, made this 10th day of September, 1996, 
between DAVID D. BOHANNON ORGANIZATION, a California corporation, herein 
referred to as "Landlord", and PERCLOSE, INC., a Delaware corporation, 
(successor in interest to Perclose, Inc., a California corporation), herein 
referred to as "Tenant".

                            RECITALS

     1.   Landlord and Tenant's predecessor in interest have previously 
entered into a Lease entitled "Business Park Lease" dated July 6, 1993 for 
demised premises (the "Premises") located at 195-199 Jefferson Drive, Menlo 
Park, California, as more particularly described in said Lease.

     2.   Landlord and Tenant's predecessor in interest have previously 
entered into a First Amendment to Lease dated January 31, 1995 (the Lease and 
First Amendment to Lease herein collectively referred to as the "Lease") 
which First Amendment to Lease demised to Tenant certain additional space 
located at 191 and 193 Jefferson Drive as more fully set out therein.

     3.   Landlord and Tenant now wish to provide for the expansion of Tenant 
into additional space located at 177 Jefferson Drive, Menlo Park, California 
and to amend the base rent due under the Lease and otherwise modify the 
Lease, all as more particularly set forth hereinbelow.

     NOW, THEREFORE, in consideration of the covenants and conditions 
contained herein, Landlord and Tenant agree to amend the Lease as follows:

     1.   Landlord hereby leases to Tenant and Tenant hereby leases from 
Landlord the Expansion Space located at 177 Jefferson Drive (hereinafter 
Expansion Space) as described in EXHIBIT "X" and shown ON EXHIBIT "X-1" 
hereto for a term commencing on September 1, 1996 and continuing through and 
including September 30, 1998. Base rent for the Expansion Space shall be set 
forth in paragraph 2 hereof.

     2.   Commencing on September 1, 1996, Tenant's base rent under the Lease 
shall increase by Forty Thousand Eight Hundred Dollars ($40,800.00) per 
annum, payable in twelve (12) equal monthly installments of Three Thousand 
Four Hundred Dollars ($3,400.00).

     The increase in base rent scheduled to occur as of October 1, 1997 with 
respect to the premises demised to Tenant under the Lease shall not apply to 
the base rent reserved hereunder for the Expansion Space which will remain 
the same throughout the demised term.

     3.   Tenant accepts the Expansion Space in its "as is" condition; 
provided that Landlord agrees to deliver the Expansion Space to Tenant with 
all electrical, plumbing and HVAC systems serving the Expansion Space in good 
working order. Any improvements to the Expansion Space shall be made by Tenant
at its sole cost and

                                       1

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expense in accordance with plans and specifications therefor which are 
subject to Landlord's prior approval.

     4.   Except as herein modified, the terms of the Lease are and shall 
remain the same.

     IN WITNESS WHEREOF, the parties have executed this Second Amendment to 
Lease as of the date first hereinabove written.


TENANT:                                  LANDLORD:

PERCLOSE, INC.,                          DAVID D. BOHANNON ORGANIZATION,
a Delaware corporation                   a California corporation



By: /s/  Kenneth E. Ludlum               By:  /s/  Robert J. Webster
   ----------------------------------        ---------------------------------
           Vice President                           Vice President


By: /s/  Kenneth E. Ludlum               By:  /s/  Ernest Lotti, Jr.
   ----------------------------------        ---------------------------------
         Assistant Secretary                      Assistant Secretary


                                       2



<PAGE>

                                 EXHIBIT "A"

                          BOHANNON INDUSTRIAL PARK

                            177 JEFFERSON DRIVE
                           MENLO PARK, CALIFORNIA

                       DESCRIPTION OF DEMISED PREMISES

                                     FOR

                                  "PERCLOSE"

   All that certain real property situate in the State of California, 
County of San Mateo, City of Menlo Park and is described as follows:

   A portion of Parcel 2, as said parcel is designated on the map entitled 
"PARCEL MAP, BEING A RESUBDIVISION OF PARCEL 2 OF P.M. REC. IN VOLUME 27 AT 
PAGE 39 AND PARCELS 2 AND 3 OF P.M. RECORDED IN VOLUME 28 AT PAGE 8, SAN 
MATEO COUNTY RECORDS BOHANNON INDUSTRIAL PARK, MENLO PARK, SAN MATEO COUNTY, 
CALIFORNIA," which map was filed in the Office of the Recorded of the County 
of San Mateo, State of California on January 12, 1976 in Volume 30 of Parcel 
Maps at Page 20, more particularly described as follows:

   Commencing at the most westerly corner of said Parcel 2, from which corner 
the point of beginning of the demised premises bears South 67 DEG. 17' East
171.00 feet and North 22 DEG. 43' East 56.00 feet; Thence from said point 
of beginning North 22 DEG. 43' East 100.00 feet; Thence South 67 DEG. 17' 
East 40.00 feet; Thence South 22 DEG. 43' West 100.00 feet; Thence North 
67 DEG. 17' West 40.00 feet to the point of beginning.

   Containing approximately 4,000 SQUARE FEET.




SEPT. 3, 1996


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                         [FLOOR PLAN]

                        JEFFERSON DRIVE


                                                              EXHIBIT "B"