1 EXHIBIT 10.80 [FERROFLUIDICS CORPORATION LETTERHEAD] MEMO OF UNDERSTANDING DATE: August 2, 1999 TO: Mr. David C. Lewandoski 31 Shipley Drive Hollis, New Hampshire 03049 This memo confirms our discussions leading to a change in your employment agreement effective August 2, 1999, as outlined below: * Your title remains Controller, and your employment with the corporation continues to be at will. * If you should be severed from the company by a corporate change in control, you will receive a lump-sum payment of six months salary. * All other benefit entitlements, with the exception of the severance payment described above, will be the same as for any other employee, and all outstanding option and stock arrangements remain unchanged. Please acknowledge your acceptance of these terms by signing below and returning one copy of this letter to Human Resources. /s/ Paul F. Avery, Jr. - ------------------------- Paul F. Avery, Jr. President & CEO ACCEPTED: /s/ David C. Lewandoski - ------------------------- David C. Lewandoski