TSA Approved Luggage Lock
The best way to protect your luggage is by locking it. In USA, you will need a TSA approved lock, meaning that if the airport security needs to open your bag, they will have a universal key to do so. In case your lock is not TSA approved, they may need to cut off your lock. Note that the airport security has the right to search your bag in case there is something suspicious. Check it here!