"Add the bROK Anti-Towing Universal Coupler Lock to your high-dollar boat trailer, and it'll keep would-be thieves at bay. This easy-to-use locking system fits all popular-sized couplers, from 1-7/8"" to 2-5/16"" ball sockets. It features a 360-swiveling, locking head for quick key access and a high-visibility red body. Built to last, the bROK Anti-Towing Universal Coupler Lock features weather- and corrosion-resistant chrome plating and powder coating finishes. Locks up your expensive boat trailer Fits 1-7/8"" to 2-5/16"" ball sockets 360-swiveling locking head High-visibility red body Weather- and corrosion-resistant Chrome plating and powder coating finishes"