Reese Towpower barrel-style (dog bone) receiver lock with sleeve is designed to secure both 5/8" and 1/2" receivers in order to deter theft. Lock includes a push-button lock mechanism which makes it easy to secure. Easy to install, the lock is for use on class I/II or III/IV receivers. Stainless steel construction includes a durable rubber cap that keeps dirt out and helps ensure a longer service life. Flat key design.