The first one I bought to use as advertised...a trailer tongue latch lock. Once I saw how limited the access is to the shackle, I bought a 2nd one to use as a lock on a link on a chain. These are not ultra-heavy duty locks, but I expect any potential thief would have to use a cutting torch or make alot of noise with a saw to get it off. The limited length of the exposed part of the shackle is the advantage of this lock. A very good value for the cost.