Trombone Blow Supporter This product reduces resistance when playing, allowing for smoother airflow and improved sound resonance. Easy to use: Simply roll the product into a tube shape as shown in the first photo and insert it into the joint on the bell side. The key is to insert it until it gently hits the end of the tube connected to the joint from the rotary side. This product can be used with instruments that use a general rotary valve. The shape is designed to fit large-bore tenor trombones and bass trombones using standard rotor valves, such as BACH 42A, B, C, 50A, B, and Edwards. While it may be possible to use it with other manufacturers' instruments, if the dimensions don't fit, you can easily cut it with scissors and adjust the shape. It cannot be used with tenor trombones or instruments with special valves. Also, we cannot answer inquiries such as "Can this be used with the △△ model from ○○ company?" There may be cleaning marks on the surface of this product, but this does not affect the quality. Please note that the perceived effects may vary from person to person.