●Scope of application: suitable for clarinet / clarinet big hug ●Features: Exquisite workmanship, small and light, easy to carry, convenient and practical. ●The inner diameter of the round mouth can be adjusted to a maximum of about 37mm (1.46"), and the inner diameter of the round mouth can be adjusted to a minimum of about 30mm (1.18") ●How to use: Unscrew the screw at the bayonet, fix the fixed port on your clarinet or clarinet, and tighten the screw. ●Reminder: Please confirm whether the outer diameter of the musical instrument tube is within 37mm before purchasing. If it exceeds this range, it cannot be used.