These SUPER CUSHION rubber caster wheels are as resilient as pneumatics with none of the maintenance problems associated with air filled wheels. They have a noise absorbing and shock isolating extra resilient soft rubber tire bonded to a thick aluminum wheel center. They are designed for use in Hospitals, Scientific and Electronic Laboratories, Department Stores, Hotels, TV and Movie Studios – wherever noise and vibration should be eliminated. They are ideally suited for moving fragile or delicate cargo.