A protective bell cover well-suited for the needs of alto saxophone, Bb clarinet, and Bb trumpet players in both rehearsal and performance. With its layer of polypropylene filtering material and unique fabric construction, this bell cover reduces the spread of aerosol particles without compromising the sonic integrity and ease of playability of your instrument. Features:- • Sonically transparent—no distortion of sound or added resistance • Reduces the spread of aerosol particles • Washable • The cover is for public non-medical use. It is not designed or intended to prevent, treat, or cure any disease or health condition.