bull-nose-ring 1)bull rings are made of brass 2)long lasting,totally proven in use. 3)thumbscrew-type locking pin, bull-nose-ring1)bull rings are made of brass2)long lasting,totally proven in use.3)thumbscrew-type locking pin,broken off when tight,reveals cross-slot for screw drivernickel-plated inside diam. 52-54 mm