| Image | Supplier | Item Code | Short Description |
|---|---|---|---|
| | GLOBAL O-RING | GOR N8-90-390 | N8-90-390, 390 BACKUP RING, NITRILE 90 DURO BLACK, 21 ID X 21-3/8 OD X 3/1 |
| | GLOBAL O-RING | GOR V8-90-390 | V8-90-390, 390 BACKUP RING, VITON 90 DURO BLACK, 21 ID X 21-3/8 OD X 3/16 |
| Inside Diameter | 21.006 in |
| Manufacturer | GLOBAL O-RING |
