Performer shows a steel ball and a metal tube to his spectators.
As the diameter of the ball is greater than the tube, it is impossible for the ball to pass through the tube.
Performer rests the ball at the edge of the tube and makes some magic passes.
The ball begins to slowly sink into the tube. After a few moments it rises from inside the tube and rests at the edge as before.
Performer can repeat this a few times, if he likes. Finally he passes the ball and tube for examination.
A very effective close up mystery. Comes with basic instructions enclosed.