SONY headphones. Used about 3 times (total usage time just over 1 hour). There are no noticeable stains or marks. Sony Model Name: WH-CH720N (Blue) No box, but I will include a separately purchased case and the instruction manual. Purchased in June 2025 from the official website for 22,000 yen. I'm not sure if it's still valid, but I'll also send the warranty with the purchase date written on it. Operation has been confirmed.