Schilke Symphony series trombone mouthpieces. The M5.1, M5.2 and M5.3 have medium shallow cups for players desiring more brilliance and projection. The D5.1, D5.2 and D5.3 mouthpieces have deeper cups, providing increased depth of sound. The * models have a more tapered throat which will feel more open and will have increased flexibility. The 6.0 models are improvements on the standard model 60 bass trombone mouthpieces.
The Denis Wick Tone Boosters are designed to fit most mouthpieces to increase the mass or weight at the cup of the mouthpiece. This allows the player to get a bit more energy into the horn without additional effort. They also help stabilize the mouthpiece to make it easier to "lock in" to the notes.