TOPTOW is a well experienced manufacturer of towing accessories. We only craft products with the best quality. TOPTOW dogbone hitch pin lock fits most ball mounts with a 5/8” pin hole and usable active length is 3-1/2" span. The lock pin is made of one piece solid hardened steel, strong and durable. All-weather rubber key slot cap keeps the key hole away from rain, snow, moisture, dust, rust, protecting the internal lock mechanism. Package includes 1x 5/8" diameter lock pin,1x lock head, 1 x rubber cap, 2x tubular round keys. This dogbone style receiver lock is compatible with hitch rack, cargo hitch tray, bike rack, hitch ball and tow rope, ensure the towing safety.