A very nicely made aluminum funnel that unscrews in the middle so that you can place a regular half dollar inside. The half dollar prevents anything from
passing through the funnel. The spectator can examine and verify this.
Now place three quarters in the top of the funnel. One quarter passes right through. Show the remaining two quarters. Again put them in the top and one passes right through.
Now take the remaining quarter and place it in your pocket. Show your hand empty. Take your empty hand and tap the top of the funnel and the spectator can hear the coin travel from your pocket through the funnel.
Now lets try all three coins at once.
Place the three coins in the funnel. Oh.. Oh.. Something is wrong, it doesn't seem to be working. After several attempts and about the time they start feeling sorry for you.
You suddenly remember that you forgot to replace the battery.
Lift up on the funnel and there sitting on the table is a battery.
The instructions recommend a AA battery for the final load. I use a C cell because it is bigger and completely fills the inside of the funnel.
The AA is easier to palm and load, but I use the C cell and if the spectators are watching too closely, I simply eliminate the kicker ending. It's still a great effect.