Lock manufacturers have made it simple to identify a Transportation Security Administration approved lock, by using one of two distinct symbols. This allows TSA to gain access into the bag without the passenger being present.
TSA Approved Lock Symbols
The symbols on the lock will either be a red boxed shape diamond, or a red torch and flame. The locks must have one of these symbols to be TSA-approved. TSA-approved locks can be purchased at most places where locks are sold. This includes Wal-Mart, Target, Home Depot, and Lowe's.
Somewhere on the lock will be a TSA code. For example, one code reads "TSA 001." This code will let Transportation Security Officers know the lock is TSA-approved and most likely will be on the bottom of the lock.
TSA Master Keys
The code on the lock will correspond to a master key. The TSA maintains secure control of the master keys and only use them if a bag inspection is needed.
The Security Process
In the event the bag needs to be physically inspected, a TSO will open it by using the appropriate key that corresponds to the code on the lock. An officer can complete his inspection and relock the bag without having the passenger present. If the lock is an unapproved lock, a TSO will cut the lock open to inspect the bag.