Automotive Tension Tools
Vehicle locks are protected by a spring-loaded dust cover which prevents dirt and moisture from penetrating into the lock.
As a result, locks which can be opened without a key are seated considerably deeper than is typical for normal lock-picking and this protection mechanism also makes the process more difficult. Vehicle lock tensioners grip the inside of the keyhole opening to keep the sightline and access to the key route permanently open, thus making it easier to concentrate on picking or decoding the lock.