This is a set of rollers to rework the center drawer of a steelcase desk with o-ring style rollers on the side drawers.  Other models of steelcase desks may use the same roller.  The steel axles that the rollers ride on are 5/16" in diameter and a little longer than 3/8 of an inch. On my desk the old rollers didn't turn freely and the friction from opening and closing the drawer wore flat spots on the rollers.