Something like a TSA key that fits the lock in addition to the owner’s key.
‘TSA approved’ locks have a seprate keyway specifically for TSA to open and inspect your bags.
There is something called ‘Master Keying’ (not talking about the master lock company), where you can setup the pins in a lock to open for multiple different keys. Commonly used in places like hotels and motels: one key only opens your door (this is the one given to you at check-in) and another key that opens all the motels locks, given to management/cleaning staff so they can get into each room without needing dozens or hundreds of keys.
This requires each lock to be explicitly setup with the correct pins to accept both keys. Not super common now, but you still find them now and again.
‘TSA approved’ locks have a seprate keyway specifically for TSA to open and inspect your bags.
There is something called ‘Master Keying’ (not talking about the master lock company), where you can setup the pins in a lock to open for multiple different keys. Commonly used in places like hotels and motels: one key only opens your door (this is the one given to you at check-in) and another key that opens all the motels locks, given to management/cleaning staff so they can get into each room without needing dozens or hundreds of keys.
This requires each lock to be explicitly setup with the correct pins to accept both keys. Not super common now, but you still find them now and again.