The Packing Cubes 3 Piece Set includes three different sized packing cubes, which are constructed from durable polyester. Each cube has an additional sleeve that allows the piece to be neatly compressed and folded into the pouch. The half of the front panel on each pouch is a mesh material for venilation. Please note that the Medium (M) and Large (L) cubes are packed into the Small (S) cube for shipping.