Yamaha s professional model background brass are world-renown for their blend of traditional warm, rich sound, combined with highly accurate intonation and easy playability. Developed in close cooperation with top artists, they represent the state-of-the-art in brass instrument design and manufacture, and are ideal for either solo performance or providing a secure foundation for any ensemble.The response of the YCB-621 is quick and secure, and the intonation extremely accurate. And the warm, rich sound has a focused tone center for superior projection. * In C * 3/4 size * Front action valves: 4 pistons * Bell: 366mm (14-3/8) * Bore: 17.5-18.5mm (0.689-.728) * Finish: Clear lacquer * Silver-plate YCB-621S * Mouthpiece: 67C4