Spirit Clock Dial - Bazar de Magic

The magician displays a clear plastic disc with large numbers printed on it and a silver arrow in the middle as if it was a clock. The magician removes the hand from the clock and brings a spectator up on stage. The spectator simply names any hour between one and 12 and the magician gives him the hand from the clock, requesting the spectator to insert it on the face of the clock and give it a spin. After several turns the hand stops exactly at the hour named by the spectator!