Protect your trailer with the Master Lock 379ATPY Universal Trailer Coupler Lock, built to help prevent unauthorized coupling when your trailer is parked, stored, or left unattended. This trailer hitch lock is simple, visible, and fits common coupler sizes, helping secure utility trailers, enclosed trailers, RVs, campers, and boat trailers. The universal design fits 1-7/8 in., 2 in., and most 2-5/16 in. couplers for home, campsite, or jobsite use. The locking mechanism resists picking and prying to help deter theft and unwanted hitching. Zinc construction resists rust and corrosion for lasting outdoor performance, a strong choice whether you're searching for a boat trailer lock, camper hitch lock, RV hitch lock, trailer tongue lock, or trailer hitch security lock. This keyed coupler lock includes two keys, so you always have a spare on hand. Whether securing a trailer between trips or adding a visible theft deterrent, the 379ATPY delivers dependable trailer security from a brand known for trusted locking products. For over 100 years, Master Lock has been helping people live safer, more secure lives. If your trailer means something, Master it. Material: Steel.