These are a pair of boxes, black and red with a complete cover. Approximately 4" in size. The magician opens the black box and inside is a red box. The red box is smaller - it is removed, and you now close the black box. Put the black box into the red box. Now the black box is smaller than the red! Repeat as often as you like. Boxes made from heavy board, Rexine coated for long life.