This well made lamp retainer ring will probably last a lifetime. Constructed of highly polished stainless, to avoid rust in an area that doesn’t get regular attention. The originals were made of chromed brass, which tended to split. The next generation were made of steel and didn’t hold up well. 3 screw holes at 120 degrees – including stainless screws. This lamp retainer ring fits Guide/BLC 682-C, 682-J, 903 and 904 headlights – and numerous other GM products that came with 7″ sealed beam lamps in the ’40’s and ’50’s.