Super Psychic Nut & Bolt

The magician hands a brass bolt and nut to the spectator and asks him/her to thread the nut onto the bolt about center. The magician holds the bolt and concentrates. Suddenly, the nut unthreads itself from the bolt! The nut and bolt can be handed out for examination. This is a classic effect with a most devious method. The workings are almost all self contained. The precision made nut and bolt do all the work!