6AN ORB Plug (14-0149) by Radium. These unique CNC billet aluminum plugs are round and use an internal hex for a compact and cosmetic appearance. Radium 14-0149 uses 9/16"-18 male port threads which are the same found on -6AN fittings.Radium 14-0150 uses 3/4"-16 male port threads which are the same found on -8AN fittings. They do not feature the 37 degree conical flare. Instead[:os:]a FKM O-ring is used for sealing. The surface is Type-II anodized with a R5 bright dipped black finish. These lightweight plugs can be used with many Radium products including: fuel rails, fuel surge tanks, fuel pressure regulators, coolant swirl tank, 4 port manifold, etc. These anodized billet aluminum adapter fittings can be used in any application using a 9/16"-18 O-ring port. This is the same thread pitch used in -6AN (ORB=O-Ring Boss). They all feature FKM (Viton) O-rings for all oil and fuel types