The magician in the hands of a few postcards. First, he shows them to the audience - let them see that they are ordinary, and then offers to break one of them. Takes a box and asks the spectator torn card to put inside. Closes the box and immediately opens again. And then pulls out a card.
Of course, you guessed that the box is not easy.
Small polished box of wood make on the principle of a cigarette case. Both parts are the same, are connected by loops.
Will still need a thin steel plate, cut out the internal size of the box and painted in the same color. Before leaving put under the plate a postcard. Turn the box - plate closes torn card and a box will appear a whole.