Rhino USA AC-TLKIT Trailer Coupler Lock Kit with Hitch Pin The heavy-duty coupler lock fits securely over the coupler, preventing unauthorized access and deterring potential theft. This kit is designed to fit most standard trailer couplers, ensuring compatibility with a wide range of trailers. The coupler lock is adjustable, allowing for a snug fit on different coupler sizes. The locks are made from a powder coated protection layer which makes the locks corrosion-resistant, ensuring their longevity and functionality even in harsh outdoor conditions.