The most important trumpet accessory is perhaps the mouth piece. Some trumpets come with a mouth piece but in the case of most trumpets, the mouth piece has to be purchased separately. Different sizes of mouth pieces are available with size 7-C being the most common one.
Another trumpet accessory which strongly influences the sound produced is the mute. A mute is a conical insert which is fitted into the bell; the function of the mute is to alter the sound of the trumpet. There are different types of mutes which produce different sounds and you can choose one according to the piece you are playing. For instance the Harmon mute which produces the buzzing sound is ideal for jazz while the cup mute is most suitable for the muffled sound. A straight, plunger, and bubble are other types of mutes. When you place the mute, make sure that it sits perfectly;otherwise, it may fall off during playing.