Lightweight 8" Bell Design The lightweight 8" bell design offers enhanced projection with a solid core. .508 Bore The .508" bore allows for a free blowing and powerful sound. Two-piece Bell The two-piece bell enable the players to deliver the brighter timbre freely. Removable Counterweight System The XO three-piece balance/counterweight system can be installed or removed with a threaded cap easily. It allows the performers to balance their instruments and offers a better playing experience. The performers can decide whether to use the counterweight system depending on their personal preferences.