SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM 8-A/A

                FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES
                    PURSUANT TO SECTION 12(b) OR 12(g) OF THE
                         SECURITIES EXCHANGE ACT OF 1934

                                 AMENDMENT NO. 1

                           KLA Instruments Corporation
             (Exact name of registrant as specified in its charter)

                 Delaware                                04-2564110
(State of incorporation or organization)               (I.R.S. Employer
                                                      Identification No.)

  160 Rio Robles, San Jose, California                       95134
 (Address of principal executive offices)                  (Zip Code)

        Securities to be registered pursuant to Section 12(b) of the Act:

  Title of each class                            Name of each exchange on which
  to be so registered                            each class is to be registered
         None                                                  None

        Securities to be registered pursuant to Section 12(g) of the Act:

                          Common Stock Purchase Rights
                                (Title of Class)





         The undersigned registrant hereby amends the following item and exhibit
of its Registration Statement on Form 8-A filed with the Securities and Exchange
Commission on March 29, 1989:

ITEM 2.  EXHIBITS.

         Exhibit No.                   Description
         -----------                   -----------

              1         Amended and Restated Rights Agreement,
                        dated as of August 30, 1995, between the
                        Registrant and The First National Bank of
                        Boston, as Rights Agent. The Amended and
                        Restated Rights Agreement includes the
                        form of Right Certificate as Exhibit A.








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                                   SIGNATURES

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this amendment to be signed on its behalf by the
undersigned hereunto duly authorized.

                                                   KLA INSTRUMENTS CORPORATION

Date:  September 25, 1995                          By:  CHRISTOPHER STODDART
                                                       ------------------------
                                                       Christopher Stoddart
                                                       Treasurer


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                                  EXHIBIT INDEX

Exhibit No.                      Description
- -----------                      -----------

1    Amended and Restated Rights Agreement, dated as of August 30, 1995, between
     the Registrant and The First National Bank of Boston, as Rights Agent. The
     Amended and Restated Rights Agreement includes the form of Right
     Certificate as Exhibit A.
                                                                 

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