This is a toilet toy featuring Shimajiro and Mimirin, which came as a bonus with Kodomo Challenge. It also includes a wall-mounting attachment. (Although my child is drawn to it, we may not use it much.) Since we rarely used it at home, it's in very clean condition. We have disinfected and cleaned the entire toy just in case. The operation has been confirmed to work without any problems. There is no deterioration observed in the battery terminal.