4D now introduces you Scratch- Off Puzzles, the greatest innovation to the jigsaw puzzle in over a decade! This patented puzzle is genius. You first assemble the puzzle, then you scratch the top layer to either mark, alter, or reveal a new image! See the magic as the image changes before your eyes. When complete, you can turn over the puzzle to retain the original puzzle art you assembled. This extra activity of fun brings a whole new dimension and education value! Product measures 18" x 24", consists of 500 PCS and comes with a Scratch Tool and a Scratch Brush.