Safe man

A sec cracker who specialises in opening strongboxes. This term seems to have entered common usage after being coined in a sketch on comedy show Two Nuns and a Eunuch, where the characters end up calling a number of famous Safe Men when searching for a locksmith.

Online, the difference between Safe men and Safe Men is considered to be as clear as if the words were spelled differently, though it isn't uncommon for the terms to be squshed.