Guerilla Painter Handy Porters - For carrying and storing paintings. Very lightweight! Constructed of sturdy 4mm corrugated cardboard with an "angular channel" design in polystyrene to protect the edges of your artwork. Each box holds two stretched canvases or four panels. Perfect for keeping your paintings dust-free while drying. Sold in packs of three, these convenient boxes are shipped flat with easy instruction for assembly and are available in 6x8, 8x10, 9x12, 11x14 and 12x16.