Mouthpiece 
Mouthpiece
Description:
It is the part of the Trumpet which is placed upon the player's lips. It's purpose is a resonator, which passes vibration from the lips to the column of air contained within the instrument, giving rise to the standing wave pattern of vibration in the air column. Mouthpieces are selected to suit the embouchure of the player, to produce certain tone, or to optimize the instrument for certain playing styles.