・ Ghost Mental Calculation Trainer for Fish Plate (Color: White) ・ 2-Digit x 2-Digit Mental Calculation in 6 Hours! Iwanami Method Ghost Mental Calculation, for Elementary School 3rd Grade and Up This is a set of two items. I bought these for my child, but they were never used. The test batteries are still inside, but they have almost no charge left (see photo 3). Operation confirmed. Stored at home for a long time. Shipped in simple packaging. Please refrain from purchasing if you are concerned about minor details, as there may be oversights due to amateur inspection. m(_ _)m Supervised by Kuniharu Iwanami, Graduate of the University of Tokyo Faculty of Medicine Recommended by Nittoken (Nihon Nōken)