swivel casters material handling casters moving dolly soft ride wheel manufacturer rubber casters SWIVEL CASTERS & RUBBER WHEELS Soft black rubber molded onto cast center, roller bearing hub ( 80 durometer Shore (A) scale). These swivel casters are ideal for heavy duty applications whenever a softer rubber wheel is required for shock absorbtion, vibration reduction and obstacle passing. Swivel raceways and wheels are equipped with grease fittings.