The circle puzzle inside a rectangle puzzle by Ravensburger. This is a Krypt Silver Blank Jigsaw Puzzle, it features 654 unique and uncommon pieces that are completely blank and silver. It’s challenging, difficult, and fun. The blank jigsaw puzzle is also high quality. It is made from extra-thick cardboard combined with fine, linen-structured paper and glare-free paper. Cool gift idea for an avid puzzle fan.