Here are some Yamaha small shank mouthpieces. I used these a few times when I was playing the euphonium, but I no longer play, so I would like to pass them on to someone who can use them. SL-51S Rim Inner Diameter...25.23 Throat Diameter...6.92 A slightly large inner rim diameter and a cup with sufficient volume for a dark tone. This is a representative model for the euphonium, with a mellow sound. This is a small shank trombone mouthpiece. The rim and inner are gold-plated. I no longer use small shank instruments, so I would like to pass them on to someone who can use them. 【Model】BACH 6 1/2AL ☆Small Shank 【Cup Depth】 MD...Slightly Deep 【Diameter】 25.40mm 【Rim】 MW...Quite Round Rim, Medium 【Features】 With the same rim and cup shape as the 6 1/2A, a larger "G" throat (6.63mm) and a #420 (darker) backbore, this combination is suitable for players seeking a Teutonic (German) tone. It has a powerful but calm roundness and is also suitable for euphonium players who want a sound that resonates well.