This SAE Standard includes couplings and hitches used in conjunction with all types of nonpassenger carrying trailers whose gross weight does not exceed 10,000 lb. This includes such types as utility, boat, camping, travel and special purpose trailers which are normally towed by the conventional passenger car and light-duty commercial vehicle. This standard is intended primarily for ball-and-socket, ring-and-pintle, and clevis-and-pin types of couplings. It should not be construed as a limitation to these three basic types alone, but should apply to any draft means designed to serve this purpose.