Computer USB Volume Controller with Customizable Shortcut Keys Adjustable Sound Control Device Default volume control function, clockwise to reduce the volume, counterclockwise to increase the volume, press the knob to mute. Compatible with a variety of system devices, suitable for mobile phones, tablets, notebooks, desktop computers, compatible with Windoens and Andriod systems. Type-C interface, plug and play. RGB lighting effect, can be turned off. The software can customize the button function: with the key value editing software, different button functions can be customized. Instructions for use: Insert the USB cable, the RGB light turns on, press the knob for 2 seconds to turn off the light, and press the knob for 2 seconds to turn on the light. Default volume control function, clockwise to reduce the volume, counterclockwise to increase the volume, press to mute. Colour:Black Material:Acrylic + Aluminum Alloy Package Contents: 1 x USB Volume Controller 1 x Type-C 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.