Kenbi Mukan, made by Bokudo Made in Showa 55 (1980) 13.5cm x 3.7cm x 1.5cm Size: 5-chogata (a unit of measurement for ink sticks) The purchase month is written on the box in pencil. It was 3000 yen at the time, but it seems to be a product that is now sold for 6050 yen.