General Pump washer 90273000 is a restop ring that is used to replace one that is worn, damaged, or causing a T Series 47 S pump to malfunction. Compatible with models T921, T1321, and T1621. It features the same construction of the original so it lasts just as long. Each pump requires three of these rings to fully service. Since this is a genuine OEM part from CAT Pumps, it is sure to fit the recommended pump models.