Each collage is 3-dimensional As shown in The Story of One Piece, each collage is done on clay-coated wooden boxes that are 2" deep. What it doesn't show is that the work continues on all sides, which gives an added dimension to each collage, as shown below. It also allows the smaller pieces to be placed on a table or mantel, as well as on the wall. ROSEWOOD 8" x 8" x 2" Sold