If I answered the question 'How do I pick a lock?' with the answer 'You already know how' I would be referring to Jiggler keys. Because if you've ever inserted the correct key into a lock such as your front door lock, only to find it didn't work, what did you do? I thought so - you gave it a jiggle, a wiggle, you moved it about a bit, and hey presto! It opened the door lock. Well that's how Jiggler keys work. They come in a variety of patterns to help 'trick' the lock into thinking it's the right key. We have jigglers for wafer locks, pin-cylinder locks, cabinet locks, and auto jigglers car locks - basically wherever they will fit. And there's often no tension tool required, as the Jiggler itself is also the tension tool.
Jiggler keys are cut in various patterns replicating the average lock settings, which means the movements outlined above - jiggling - cause the pins or wafers to be set until the lock opens. Any good locksmith will have a selection of auto Jigglers, but I would also say they also offer a great way of lock picking for beginners.