The Eastman EEP826S Professional Compensating Euphonium is a top-tier Bb instrument designed for professional performance with a rich, warm, and dark sound. Featuring a fully compensating system, it offers precise intonation, a .591″ bore, a 4th valve bore of .610″, and an 11-1/2″ upright yellow brass bell, usually finished in silver plating with gold-plated accents