COMP's Positive Stop PTFE valve seals offer more clearance for dual springs with better sealing than o-ring or umbrella seals. These 503 seals have a .630" outer diameter and fit applications with 11/32" valves and .530" OD valve guides.
Available individually under 503-1, in a set of 8 under 503-8, in a set of 16 under 503-16
Engines w/ 0.530" OD Valve Guides and 11/32" Valve Stems