Trombone Blow Supporter Inserting this product deep into the joint between the bell and slide reduces resistance when playing, smoothing the airflow and improving the resonance of the sound. Inspired by the acoustic sleeve included with the BACH La Rosa model, this product was developed after careful consideration of materials and shape, with the cooperation of over ten professionals and amateurs. Everyone who assisted in the development reported noticeable changes in sound and playing feel, and gave it high praise. It can be attached to instruments using a general rotary valve. The shape is designed to fit large-bore tenor trombones and basses using general rotary valves, such as BACH 42A, B, C, 50A, B, Getzen, and Edwards. While it should be possible to attach it to other manufacturers' instruments, if the dimensions don't fit, you can easily cut it with scissors and adjust the shape for use. It cannot be used on tenor trombones or instruments using special valves. Also, we cannot answer inquiries such as "Can it be used on the △△ model of ○○ company?" Cleaning marks may remain 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.