Tente Heavy Duty Plate Castor, Polyurethane Tyre. These heavy-duty castors from Tente are made from heavy sheet steel, with a broad reinforced fork and two ball races. The wheel has an aluminium body and precision ball bearing, and is made from polyurethane for durability. These castors are available as swivel, braked and fixed, in various wheel sizes. Features and Benefits. Steel sheet Broad reinforced fork Two ball races Swivel, braked and fixed castors Aluminium wheel body PUR casted tread Precision ball bearing A range of wheel diameter sizes Rectangular plate according to EN-R 42/43 Shore A92