This is the EIKO (Seiko) ST300, a tuner specifically for Taishogoto. It's a product that allows tuning with simple switch operations, suitable for beginners to advanced players. This item was at my grandmother's house. It is a used item. Operation has been confirmed, and a 9V battery is included, although the remaining charge is unknown. The instruction manual and storage bag are included. While it doesn't show much wear, there are some minor scratches from use. Details such as the purchase date and frequency of use are unknown. Thank you for looking.