1.WIDE APPLICATION: USB volume control knob is compatible with multiple systems, supports for Android and Windows systems, and is compatible with mobile phones, tablets, laptops, and desktop computers. 2.FUNCTIONS AND USES: USB volume controller can directly control the volume of the computer operating system, can be customized, support shortcut keys. 3.EASY TO USE: There is no need to install any drivers or software on your computer to drive this volume regulator, and can be used after plugging in the device. 1.WIDE APPLICATION: USB volume control knob is compatible with multiple systems, supports for Android and Windows systems, and is compatible with mobile phones, tablets, laptops, and desktop computers. 2.FUNCTIONS AND USES: USB volume controller can directly control the volume of the computer operating system, can be customized, support shortcut keys. 3.EASY TO USE: There is no need to install any drivers or software on your computer to drive this volume regulator, and can be used after plugging in the device. Item Type: USB Volume Control Knob Features: Custom; Support shortcut keys Support: For Android systems, Windows systems Color: Black Material: plastic Package Contents: 1*Volume Controller 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.