Snapper Puzzle (1497)

A small cylinder with a hole with elastic band running through it. A small stick with a hook is inserted into the cylinder, apparently threading the rubber band over the hook. When the cap is pulled out and released, the plunger is snapped into the cylinder by the action of the elastic. When given to a spectator to try, he just cannot thread the hook into the elastic. Impossible, till you learn the simple, but clever secret. Showcard blister packing with instructions.