Radium Engineering 12AN ORB Plug
The 1-1/16"-12 threaded adapter fittings are compatible with 12AN ORB (O-ring boss) ports. Because the threads on these fittings are not used for sealing, PTFE paste or thread sealant is not required. The FKM O-ring should be lubricated with engine oil.
ORB ports are an industry standard and found on many automotive plumbing products, including most Radium products. All fittings include FKM O-rings.