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                                                                   Exhibit 10.19

          Amendments to the Varco International, Inc. 1990 Stock Option Plan

          WHEREAS,   the Board of Directors of the Corporation deem it desirable
          and in the best interests of the Corporation and its shareholders that
          the Corporation's 1990 Stock Option Plan (the "Plan") be amended in
          certain respects;

          NOW, THEREFORE, BE IT RESOLVED, that paragraph F of Section 6(b) of
          the Plan be, and the same hereby is, amended to read in its entirety
          as follows:

               F.   Other Severance.  In the event an employee's employment with
          Varco and its subsidiaries is terminated for any reason other than as
          set forth in paragraphs D and E above, any Nonstatutory Option which
          he holds may be exercised, to the extent it was exercisable on the
          date of termination of his employment, within such period after the
          date of termination of his employment (not to exceed ninety (90) days)
          as the Committee shall prescribe in his option agreement. For purposes
          of this Paragraph F, an employee's employment shall be deemed to have
          terminated on the earlier of the date his employment terminates or the
          date he receives written notice that his employment is or will be
          terminated. Such Option shall expire upon the expiration of such
          period unless the employee dies prior thereto, in which event he shall
          be deemed to have died on the date his employment terminated;
          provided, however, in no event shall such Option be exercised more
          than ten years from the date such Option was granted.

     and further

          RESOLVED, that paragraph  F of Section 6(c) of the Plan be, and the
          same hereby is, amended to read in its entirety as follows:

               F. Other Severance.  In the event an employee's employment with
          Varco and its subsidiaries is terminated for any reason other than as
          set forth in paragraphs D and E above, any Incentive Stock Option
          which he holds may be exercised, to the extent it was exercisable on
          the date of termination of his employment, within such period after
          the date of termination of his employment (not to exceed ninety (90)
          days) as the Committee shall prescribe in his option agreement. For
          purposes of this Paragraph F, an employee's employment shall be deemed
          to have terminated on the earlier of the date his employment
          terminates or the date he receives written notice that his employment
          is or will be terminated. Such Option shall expire upon the expiration
          of such period unless the employee dies prior thereto, in which event
          he shall be deemed to have died on the date his employment terminated;
          provided, however, in no event shall such Option be exercised more
          than ten years from the date such Option was granted.

          and further

          RESOLVED, that the Compensation Committee of the Board of Directors,
          as the Committee under the Plan, is authorized, in its sole discretion
          and from time to time, to amend any option outstanding under the Plan
          in a manner consistent with the foregoing amendments to the Plan; and

          RESOLVED, that each of the officers of the Corporation be, and he
          hereby is, authorized and directed to perform all acts and to execute
          and deliver all
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          certificates and documents and to take or cause to be taken all other
          action as any such officer may deem necessary or appropriate to carry
          out the foregoing resolutions and to comply with the terms and
          provisions of the Plan.