Our standard tuba mouthpieces are arranged in a logical ascending order from deep to shallow and wide to narrow in three different types; N, W, & H. This arrangement permits players to select a mouthpiece by precise increments of depth to find the correct cup volume required by their musical needs. 'H' pieces have a smaller inside bite. Outside Cup Diameter: 1.873" (47.57mm) Inside Cup Diameter: 1.325" (33.60mm) Cup Depth: 1.632" (41.45mm) Drill Venturi: 0.328" (8.33mm) Length: 3.800" (96.52mm)