Made from 6061 so welding and anodizing after welding is no issue for the do it yourselfer. Female bung is NPT thread which allows a racer to use a standard 37 degree JIC flare/NPT fitting if they choose.
Bungs have step on the back side which allow the bung to register in the hole and makes it easy for alignment and to be welded from both sides if the racer chooses.
Racer can pick fitting size from drop down menu.