This is a puzzle with various combinations. I'm selling it because I don't play it anymore. It was about 900 yen originally. From the website below: "Recommended as an educational toy for kindergartens and nurseries. Difficulty level 2, suitable for beginners to intermediate players. There are 2,339 ways to fit the pieces, but finding just one of them is a challenge. "Pentomino" has a comfortable balance of "fun" and "difficulty," and is a masterpiece puzzle that allows you to challenge many combinations. Enjoy the ultimate puzzle mystery woven by just 12 pieces, putting them in and taking them out, reasoning and rearranging."