These ball mounts feature two heavy-duty polyurethane cushions in the rear retainer to reduce the slams and bangs associated with trailer towing during starting, stopping and rough highways. Reducing these jolts helps to protect your towing vehicle's driveline, hitch assembly and trailer contents. Fits most underframe receiver hitches with 2 square socket. Class IV rated for 10,000 lb. maximum gross towing weight and 2,000 lb. tongue weight. 1 diameter ball hole. Made in USA. Sizes: 2 drop, 4 drop, 6 drop, 8 drop. Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Type: Ball Mounts.