Default volume control function, clockwise to reduce the volume, counterclockwise to increase the volume, press the knob to mute.<br> Compatible with a variety of system devices, suitable for mobile phones, tablets, , desktop computers, compatible with Windoens and Andriod systems.<br> Type-C interface, plug and play.<br> RGB lighting effect, can be turned off.<br> The software can customize the button function: with the key value editing software, different button functions can be customized.<br> <br> 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.<br> Colour:Black<br> Material:Acrylic + Aluminum Alloy<br> <br> Package Contents:<br> 1 x USB Volume Controller<br> 1 x Type-C Cable<br> <br> Only the above package content, other products are not included.<br> 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.