Set of 6 Heavy Duty casters for the 7 FT Midnight Pro Series Workbench, or the 9FT Midnight Pro Series Workbench. Each caster is a 4 bolt plate caster. The 4 swivel locking casters go on the corners and 2 non-locking swivels on the center. All casters have grease fittings for maintenance. Box also includes all mounting hardware including 24 M-10 Bolts, lock washers and regular washers.