This Wardrobe Roller has a 2-1/4" (57 mm) wide, top mounted, stamped steel top hung adjustable roller bracket which also acts as a corner bracket for steel frame bi-pass doors. It has a single, 7/8" (22 mm) diameter, round edge nylon roller.  Fits on Acme doors.  Two rollers per package

Replacement top roller
Adjustable
Steel casing
Nylon guide
Supplied in pairs