360-degree rotatable arc button, easy to use (volume adjustment, mute, up and down, pause), and avoid discomfort caused by edges. Computer sound desktop control. Quickly adjust the volume, say goodbye to the mouse and keyboard, rotate the button to quickly adjust the computer volume. connect to a Bluetooth-compatible speaker, the computer sound is transmitted to the Bluetooth-compatible speaker/amplifier, and the endless songs and music in the Internet world can be transmitted to the speaker and power amplifier. enjoy the charm of music. External sound card mode. The computer is equipped with an external sound card, without loss of sound quality. Small and easy to go. Less than the size of a mobile phone, suitable for office work, easy to carry Color: Black Material: plastic Package Contents: 1 x USB Computer Volume Controller 1 x cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.