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                                                                  EXHIBIT (a)(4)

[WYNN'S LETTERHEAD]

                                                                   June 22, 2000

Dear Fellow Stockholder:

     I am pleased to inform you that on June 13, 2000, our Company signed an
agreement to be acquired by Parker-Hannifin Corporation. The consideration to be
received is $23.00 cash per share of common stock. This offer represents a 70%
premium to the Company's closing stock price on June 13, 2000, the day our Board
of Directors approved the sale to Parker-Hannifin.

     Our Board of Directors carefully considered many factors when it decided to
recommend Parker-Hannifin's offer. These factors are more fully described in the
enclosed 14D-9. After such consideration, our Board of Directors unanimously
recommends that you accept Parker-Hannifin's offer and immediately tender your
shares to Parker-Hannifin. The tender offer is currently scheduled to expire at
12:00 midnight, New York City time, on July 20, 2000.

     Accompanying this letter is:

          1. A copy of our Solicitation/Recommendation Statement on Schedule
     14D-9; and

          2. Parker-Hannifin's Offer to Purchase and related materials,
     including a Letter of Transmittal for you to use in tendering your shares.

     Included as Schedule II to the Recommendation is a copy of the written
opinion dated June 13, 2000 of J.P. Morgan Securities Inc., the Company's
financial advisor, to the effect that, the cash consideration offered to holders
of the Company's common stock is fair to the stockholders from a financial point
of view.

     We urge you to read the enclosed materials carefully.

     On behalf of your Board of Directors, I thank you for your continued
support.

                                          On behalf of the Board of Directors,

                                      /s/ JAMES CARROLL
                                          James Carroll
                                          Chairman of the Board and
                                          Chief Executive Officer