This Yamaha YEP-642S Neo Bb-Euphonium is a top-quality musical instrument for euphonium players. With its silver-plated finish, this euphonium looks sleek and modern. The body material is made of brass, specifically yellow brass, and the bell material is also made of brass. The bore size is between 15-16.8 mm, which is perfect for producing a warm and rich tone.This euphonium has four piston valves and is in the key of Bb. Its bell diameter is 11.8 inches, making it easy to handle and play. The instrument is a standard type and is suitable for both beginners and professionals. Whether youre playing in a concert hall or practicing at home, this Yamaha euphonium is the perfect choice for any euphonium player.Instrument has 1 mostly noticeable scratch on backside but other than that it looks and plays like new.Will send more pictures if asked.