These were made on original Brooklyn tooling. These used the old Gretsch process: Hand polished first, then copper plating, then nickel plating, then bright chrome plating. Very rare. Made from old Gretsch USA tooling and same exact hoop as used on all the great Gretsch drums of the '60s through 2000'.  
Text from Original Gretsch Catalog: "Gretsch was the first drum manufacturer to produce die-cast hoops, and the first to offer them as standard equipment. Die-Cast hoops are truer round, which enables them to be tuned accurately with a consistent tension over the entire batter head."