Our secure locking devices have an enhanced performance tamper evident material that shows a clear void or open security message when the label is lifted. Initially developed for use on the doors and hatches of aircraft when they are parked overnight or in flight, however these locking devices are ideally suited for use on most surfaces. This product gives visual evidence of tampering or illegal entrance on aircraft, vehicles, doors, sensitive equipment, lockers, containers, restricted areas, etc. These security locking devices are great for travel.