Sounding invisible matches

Effect: 

-The magician shows an empty matchbox, but when he shakes it, it sound like a full of matches one.

Materials: 

- 2 matchboxes

- an elastic rubber band

Presentation and  Secret:

The performer picks a matchbox, shakes it, and it sounds like a regular one, but when he opens the box, it is empty! The matches are gone.

The secret is in wrapping the rubber band around your wrist, and with it holding the regular matchbox, hiding it with the sleeve.

Then, when you  shake the empty box, you move the other box too, so it sounds under the sleeve.