This is the Curt Manufacturing Brass-Plated Trailer Coupler Lock, a versatile and durable solution for securing a variety of trailer couplers. This lock features a 1/4" diameter hardened steel locking pin with a 3/4" span, making it compatible with boat trailers, enclosed trailers, utility trailers, and more. Designed with a weather-resistant brass-plated finish, this trailer lock offers long-lasting protection against the elements. This set includes two keys for added convenience, and operating the lock is simple; simply insert the key and turn to lock or unlock the assembly. This padlock is a great choice for uses beyond just trailer couplers, you can use it as a door latch lock for campers, RVs, and enclosed trailer doors; or other purposes! Plus, Curt Manufacturing backs this trailer padlock with a Limited Lifetime Warranty (one-year finish, one-year parts).