Note from Martin:

Very easy yet incredibly baffling magic that sells on sight when demonstrated in our London shop.

 

This incredible little trick with a nut, a bolt & a tube. The nut is screwed halfway onto the bolt and dropped into a small plastic tube. The Magician now gives the tube a little shake and simply tips the contents out - to the audience's complete astonishment, the nut has not only unscrewed itself, but has penetrated right through the head of the bolt and rolls out of the tube separately. Everything is immediately dropped into the spectator's hand for thorough examination.