Before I bolted mine to the wall and floor (the wife was pissed about me cutting the rug away), I mounted four case-hardened U-bolts flush to the wall with case-hardened chains so that I could lock an "X" pattern over the door. I use them when we are away, as the locks are good enough for keeping the guns away from the kids. Just a bit more discouragement for the wielder of a crowbar.