A. The trumpet mouthpieces are made of brass, providing a comfortable touch and a nice tone. The thick silver-plated surface is easy to wipe and keep clean. B. The set contains 3 trumpet mouthpieces (1 7C, 1 5C, and 1 3C). This set can meet the requirements of different situations and learners. C. The 3 sizes of trumpet mouthpieces, from the smallest to the largest, are hard to distinguish with the naked eye, including the outer ring, inner cup, inner diameter, and inner tube. However, the engraved model helps to clearly tell different types apart in a short time. D. If you're a beginner, you may start with the 7C mouthpiece, which makes it easier to produce sound when playing. After practice, when your lip muscles get stronger, you can think about switching to the 5C mouthpiece and then to the 3C mouthpiece. The 3C mouthpiece is suitable for trumpet players with more experience. E. These instrument accessories are compatible with most standard trumpets. They can meet the needs of different occasions, such as schools, concert halls, bars, homes, band practice areas, as well as the learning needs of players. F. Color: Silver G. Material: Brass H. Package contents: - 1 7C mouthpiece - 1 5C mouthpiece - 1 3C mouthpiece Only the above items are included in the package, and no other products are provided. I. Notes: Light reflection and different monitors may cause slight differences between the color of the item in the picture and the actual product. A measurement error of ±1 - 3 cm is acceptable.