The Marcinkiewicz mouthpieces are highly respected in the brass player community. These tuba mouthpieces are exceptional and used by many famous players. Marcinkiewicz Tuba Mouthpieces Cup Selection The 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. Please note that the chart is grouped in sections according to type. This arrangement permits players to select a mouthpiece by precise increments of depth to find the correct cup volume required by their musical needs.Rim Selection 'N' mouthpieces have a narrow rim, 'W' pieces have a wider rim and 'H' pieces have a smaller inside bite. The ST3 and ST4, with shallower cups, are designed specifically for students. (It doesn't have to hurt to play!)Comparison Notes Models given for comparison again reflect standard sizes. These are not copies; substantial changes and improvements have been made to increase playability and response.