This is a 60-day simple calculation drill book for adults to train the brain, by Professor Ryuta Kawashima. I've only flipped through it once. There are some minor scratches on the cover. The text inside is clean. The paper clip in the photo is not included. Please refrain from purchasing if you are concerned about used items, as this has been stored at home. Thank you for your understanding. Please do not ask for reservations or holds. I cannot respond to price negotiations due to using a PC. The listing may end suddenly if the item sells elsewhere. Thank you for your understanding.