<PAGE>
NOTICE OF GUARANTEED DELIVERY
FOR
TENDER OF SHARES OF COMMON STOCK
(INCLUDING THE ASSOCIATED PREFERRED STOCK PURCHASE RIGHTS)
OF
SUMMIT AUTONOMOUS INC.
(FORMERLY KNOWN AS SUMMIT TECHNOLOGY, INC.)
(NOT TO BE USED FOR SIGNATURE GUARANTEES)
As set forth in Section 2 of the Offer to Purchase (as defined below), this
form or one substantially equivalent hereto must be used to accept the Offer (as
defined below) if certificates representing shares of Common Stock, par value
$0.01 per share (the "Shares"), of Summit Autonomous Inc., a Massachusetts
corporation (the "Company"), together with the associated rights (the "Rights")
to purchase Series A Preferred Stock, par value $0.01 per share, issued pursuant
to the Rights Agreement dated as of March 28, 2000, between the Company and
Fleet National Bank (as amended from time to time, the "Rights Agreement") are
not immediately available or if the procedures for book-entry transfer cannot be
completed on a timely basis or time will not permit all required documents to
reach the Depositary prior to the Expiration Date (as defined in the Offer to
Purchase). Unless the context otherwise requires, all references herein to the
Shares shall be deemed to include the Rights, and all references to the Rights
include the benefits that may inure to holders of Rights pursuant to the Rights
Agreement. This form may be delivered by hand to the Depositary or transmitted
by telegram, facsimile transmission or mail to the Depositary and must include a
guarantee by an Eligible Institution (as defined in the Offer to Purchase). See
Section 2 of the Offer to Purchase.
THE DEPOSITARY:
CHASEMELLON SHAREHOLDER SERVICES, L.L.C.
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BY MAIL: BY OVERNIGHT COURIER: BY HAND:
Reorganization Department Reorganization Department Reorganization Department
P.O. Box 3301 85 Challenger Road 120 Broadway
South Hackensack, NJ 07606 Mail Stop--Reorg 13th Floor
Ridgefield Park, NJ 07660 New York, NY 10271
BY FACSIMILE TRANSMISSION:
(201) 296-4293
(FOR ELIGIBLE INSTITUTIONS ONLY)
CONFIRM BY TELEPHONE:
(201) 296-4860
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DELIVERY OF THIS INSTRUMENT TO AN ADDRESS, OR TRANSMISSION OF INSTRUCTIONS
VIA A FACSIMILE NUMBER, OTHER THAN AS SET FORTH ABOVE, DOES NOT CONSTITUTE A
VALID DELIVERY.
THIS FORM IS NOT TO BE USED TO GUARANTEE SIGNATURES. IF A SIGNATURE ON A
LETTER OF TRANSMITTAL IS REQUIRED TO BE GUARANTEED BY AN ELIGIBLE INSTITUTION
UNDER THE INSTRUCTIONS THERETO, SUCH SIGNATURE GUARANTEE MUST APPEAR IN THE
APPLICABLE SPACE PROVIDED IN THE SIGNATURE BOX ON THE LETTER OF TRANSMITTAL.
THE GUARANTEE ON THE REVERSE SIDE MUST BE COMPLETED.
<PAGE>
Ladies and Gentlemen:
The undersigned hereby tenders to Alcon Acquisition Corp., a Massachusetts
corporation (the "Purchaser") and a wholly owned subsidiary of Alcon
Holdings Inc., a Delaware corporation, upon the terms and subject to the
conditions set forth in the Purchaser's Offer to Purchase dated June 5, 2000
(the "Offer to Purchase") and in the related Letter of Transmittal (which,
together with any amendments or supplements thereto, collectively constitute the
"Offer"), receipt of which is hereby acknowledged, the number of Shares set
forth below, all pursuant to the guaranteed delivery procedures set forth in
Section 2 of the Offer to Purchase.
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Name(s) of Record Holder(s): ___________________________________________________
Please Print
Address(es): ___________________________________________________________________
________________________________________________________________________________
Zip Code
Daytime Area Code and Tel. No.: ________________________________________________
Signature(s):
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Number of Shares: ______________________________________________________________
Certificate Nos. (if available): _______________________________________________
(Check box if Shares will be tendered by book-entry transfer)
/ / The Depository Trust Company
Account Number: ________________________________________________________________
Transaction Code No.: __________________________________________________________
Dated:__________________________________________________________________________
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<PAGE>
GUARANTEE
(NOT TO BE USED FOR SIGNATURE GUARANTEE)
The undersigned, a firm that is a participant in the Security Transfer
Agents Medallion Program, the New York Stock Exchange Medallion Signature
Guarantee Program or the Stock Exchange Medallion Program, hereby guarantees to
deliver to the Depositary either the certificates representing the Shares
tendered hereby, in proper form for transfer, or a Book-Entry Confirmation (as
defined in the Offer to Purchase) with respect to such Shares, in any such case
together with a properly completed and duly executed Letter of Transmittal (or a
facsimile thereof), with any required signature guarantees, or an Agent's
Message (as defined in the Offer to Purchase), and any other required documents,
within three trading days (as defined in the Letter of Transmittal) after the
date hereof.
The Eligible Institution that completes this form must communicate the
guarantee to the Depositary and must deliver the Letter of Transmittal and
certificates for Shares to the Depositary within the time period shown herein.
Failure to do so could result in a financial loss to such Eligible Institution.
---------------------------------------------
Name of Firm: ______________________________________________________________
Address: ___________________________________________________________________
____________________________________________________________________________
____________________________________________________________________________
Zip Code
Area Code and Tel. No: _____________________________________________________
---------------------------------------------
---------------------------------------------
Authorized Signature: ______________________________________________________
Name: ______________________________________________________________________
Please Type or Print
Title: _____________________________________________________________________
Dated: _____________________________________________________________________
----------------------------------------------
NOTE: DO NOT SEND CERTIFICATES FOR SHARES WITH THIS NOTICE. CERTIFICATES
FOR SHARES SHOULD BE SENT WITH YOUR LETTER OF TRANSMITTAL.
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