When travel via air, carry-on are restrictive, but checking-in comes with the worry of lost or, worst, being looted. They are so vulnerable. What if a stranger reaches in? Are my jewlery safe? They may touch my underwear!
TSA may cut off locks for random inspection.
The humble cable ties are pennies per pound. The smallest one withstands the strongest fingers, yet yield to the least threatening cutting tool. It is basically temper-proof, also colorful as an identification device.
Throw a bunch into the hand-carry bag. Tie your check-in luggage at the counter and board with a peace of mind.