Golden Key

An ancient golden key capable of opening any door is shown on your fingertips. Explaining that some doors are different from others, you sometimes have to move the teeth on the key to compensate. To demonstrate this you slide the teeth of the key in a circular manner and then proceed to move the teeth halfway down the shaft of the key. Further explaining that the key only works for it's owner, you hand the key over and nothing the spectator does will be able to move the teeth of the key. They are frozen at your command! There is truly nothing for the spectator to find and the teeth of the key will only move for you. Truly Amazing!