The safes are different on the newer ships. Old ones used a 4 digit code and the newer ships use any card with the black stripe on the back.....even a grocery card will work. BUT you never get a key from the steward......he may have an over-ride to get into it if was left locked from previous guests ( we had that happen), but as soon as you use another card it will change. I believe they have to have the purser come and do an over-ride for the safes. NEED a witness to open them otherwise.