Catch Can O-Ring Service Kit Radium Engineering - USA-RAD-20-0057 - The 20-0057 Catch Can O-Ring Service Kit is compatible with Radium Engineering standard catch cans, including all Fluid Lock® (FL) catch cans. It is NOT compatible with the Radium Engineering AOS-R or large Competition Catch Cans. INCLUDES-2x small dipstick O-rings (approx. 0.27" diameter)-2x catch can canister O-rings (approx. 2.1" diameter)