Kingpinless caster rigs are different from standard kingpin caster rigs in that the swivel section is held together without a rivet or nut and bolt kingpin. Kingpinless caster rigs are held together by a single row of ball bearings that are contained by a full contact interlocking swivel raceway design. Kingpinless casters are ideal for towing, conveyor, maintenance/utility carts, tow lines, drag lines and more robust applications seen in industrial environments.
For more info, check out Caster Rig Types.