Patents Reinstated Due to the Acceptance of a
                      Late Maintenance Fee From 12/19/97

Patent           Serial            Filing          Issue          Granted
Number           Number            Date            Date           Date

4,430,524        06/360,198        03/22/82        02/07/84       12/22/97
4,493,623        06/468,066        02/22/83        01/15/85       12/22/97
4,842,530        07/149,572        01/28/88        06/27/89       12/22/97
5,130,893        07/630,647        12/20/90        07/14/92       12/23/97
5,196,238        07/660,370        02/25/91        03/23/93       12/22/97