1. USB plug and play, no driver required, compatible with Windows, Android, Mac/IOS system 2. No mouse, quickly adjust the volume without affecting the current work window 3. All-in-one design, fixed USB cable, prevent falling off, easy to use 4. Aluminum alloy metal shell, matte anti-fingerprint, non-slip rotary button 5. 360-degree arbitrary rotation to adjust the volume, easy to use 6. 4 soft cushions at the bottom, stable and non-slip when using it 7. Functions: volume adjustment, mute, up and down, pause 8. Size: about 2.4 x 1inch
