Reese 5973 Bulldog Remov-A-Ball 2-5/16" Replacement Ball Allows unrestricted use of pickup bed area hauling cargo 2-5/16" forged, heat-treated zinc ball standard Spring-loaded chrome sliding pin and safety chain ensures positive lock Magnetic cover protects ball hole and activating lever slot when not in use In-truck platform can be used with rail kits or installed on any vehicle, providing adequate structure to secure the platform