Bulldog 580404 Chrome Universal Chrome 5/8" Trailer Dogbone/Coupler Lock Set Bulldog Lifelong locks feature stronger break resistance, a dual self-locking design, and a high security square key design Highly polished chrome plated lock components are strong yet attractive - strength doesn't have to be ugly Ball bearing locking mechanism; dust cap protects lock mechanism from the elements Set includes Class III/IV 5/8 inch chrome Dogbone lock and chrome coupler lock; keyed alike; comes with 2 keys Backed by Bulldog's Lifetime Limited Warranty