ID-5.25 Nominal CS-1/8" 95A Urethane Flat Back Up Inch

These Urethane back up rings are specifically sized for O-rings. Dash sizes are equivalent to AS568A O-ring sizes. For metric sizes see MBH type backups. They are highly extrusion resistant and are compatible with water and petroleum based fluids up to temperatures of 275°F. Unlike TFE, they can be stretched over larger diameters and will quickly return to their original size. Temperature: -40° to 275°F