This Closet Door Nylon Roller has an adjustable, 1/2" (12.7 mm) back offset, top hung, side mounted stamped steel bracket with tandem, 7/8" (22.2 mm) diameter, and round edge nylon wheels. The roller fits on 3/4" to 1-3/8" (19 to 35 mm) thick doors used on Stanley, Cox and Acme track systems.