Casters may be designed to rotate, or “swivel,” about a vertical axis (termed “swivel” casters), or they may be fixed (termed “rigid” casters). Conventional swivel casters generally Perfect Steerable Transfer Cartlude a horn that is rotatably coupled to a swivel plate, which in turn is mounted to a vehicle, such that the horn and caster wheel may swivel about a vertical swivel axis relative to the swivel