90A Durometer Urethane Back-Up Rings -115 Dash Size, Per Pack

Back-up rings sit behind the O-ring in the groove, on the low-pressure side. Because these are molded urethane, you can stretch them enough to get them seated without much fuss, and they snap back to shape pretty quick once they're in place. Sizes line up directly with standard O-ring dash sizes, so if you know your O-ring size, you've got your back-up ring size.

These rings are sized to correspond with standard O-ring dash sizes, so these -115 rings will work with a -115 O-ring.