The alliance brass david childs signature euphonium mouthpiece4 is a mouthpiece that offers ultimate craftsmanship for trombone and euphonium players seeking to achieve a blend of delicate articulation with a focused and brilliant tonal quality especially in the high registers favoured by david childs himself for trombone performances. With a cup diameter of 25.75 mm a rim of 6.73 mm and a bore of 7.4 mm coupled with a deep cup it offers players a rich sonorous foundation upon which to build their sound. The unique design allows seamless transitions across ranges while ensuring that each note is delivered with clarity and impact. Its an invaluable tool for those who wish to elevate their musical expression providing unparalleled control and responsiveness.