1.Improving the accuracy of keys: This small valve helps to improve the accuracy of keys, improve the smoothness of performance, and make the sound produced by instrument users more beautiful. 2.Applicable scenario: This horn valve is used to replace old, damaged, and missing buttons, so if you happen to have this requirement, then this is prepared for you. 3.Convenient Storage: The horn valve is very easy to store, so you dont have to worry about the speaker valve button occupying space 4.Convenient to carry: The horn valve has a small volume and can be carried with you when needed, and can be replaced in a timely manner 5.Attention: Please confirm the size of your product before purchasing to avoid unpleasant shopping experiences