Trombone Mouthpiece (Small Bore) willie's W3 Art'sOpus S4 This is a signature model for trombonist Hiroyuki Matsushita (Lecturer at Osaka College of Music). It is ideal for alto trombone or for playing on a small bore trombone. The rim size is about 6 1/2, and the cup is slightly thicker, with a characteristic thick and stable sound. It has the excellent articulation unique to willie's. I bought it new, but I only tried it out at the music store and haven't used it much since then. It has been carefully cleaned and stored. I think the condition is relatively quite good. The new price including tax is 36,300 yen.