Dummy radiator neck

Occasionally someone finds themselves with a presurized radiator and needs a stock neck to pass through the shell to hold their cap or mascot. Most commonly these are 2-1/4" OD and 1" tall with a base plate. When twisting the cap, the bayonet cup inside will ride the ramps and tighten as it goes. If its different please provide the height from the top of the neck the underside of the shell and the OD of the neck hole and we will customize to fit.