Do not use these to secure anything you wouldent put a please rob me sign on. These can easily be opened in less than 10 seconds. You can open one with a soda can and some scissors. Even the heavy duty ones can easily be cracked. It only takes me around one minute to make the shim and open the lock (only 6 seconds for the lock part). They are pretty much useless. Just thought I would let yall know.