A large bass trombone mouthpiece, larger than a Bach 1G, but smaller than a Schilke 59. • 28.30mm cup diameter. • 7.92mm (0.312") throat bore. • Gold plated. The Griego Nouveau series was created to give players the flexibility of a lighter mouthpiece. It provides a width of sound and wider partial feel for a natural playing experience. Every tone and timbre can be manipulated, making the Nouveau a very expressive mouthpiece. - the manufacturer