A bottle with a silk knotted on the top and a tube which is the cover for the bottle and a wand are on your table. The magician unfastens the knot on silk from the bottle and then shows the tube completely empty to the audience and puts it over the bottle.
Instantaneously, the magician makes the silk vanish with his wand. Afterwards, he removes the tube from the bottle, and is astonished to see the knot has been fastened back to the top of the bottle.
The wand is made of aluminum. The bottle is made of metal and the tube is plastic.