Marcinkiewicz 9B mouthpiece for trombone, model Bob Stroup, small shank, outside cup diameter 39,24 mm (1,545in.), inside cup diameter 26,06 mm (1,026 in.), cup depth 27,71 mm (1,091 in.), drill venturi 6,35 mm (0,250 in.), length 79,76 mm (3,140 in.), silver plated, comparsion only with Bach 5