A tray puzzle is made up of a board with a recessed center with a raised edge frame, plus removable puzzle pieces. This allows the durable puzzle pieces to fit into the tray creating one flat surface when completed, just like a regular jigsaw puzzle. When the puzzle pieces are removed from the board, you’ll find a greyed-out image as the background. This greyed-out image also has definitive lines to give the puzzler two clues: the shape of the puzzle piece and the image printed on it.