Equipment for railroad cars, namely, couplers, knuckles, coupler components, namely, knuckle locks, knuckle throwers, lock-lift assemblies, locks, knuckle pins, cotter pins for use with knuckle pin, assembled coupler systems comprised of couplers, knuckles, knuckle locks, knuckle throwers, lock-lift assemblies, locks, knuckle pins, cotter pins for use with knuckle pin