Features: 1.Support one?key mute function, just press the knob to enter the mute state immediately, press again to restore the sound, simple and convenient to use. 2.USB connection, plug and play, once connect computer power, you can turn the knob to easily and quickly adjust the computer's volume. 3.The external volume control knob is specially designed for computers and is compatible with Win 10/8/7/Vista/XP/ OS X. 4.Equipped with a USB cable, about 2 meters/6.6 feet long, suitable for use with a desktop or laptop computer. 5.With metal shell, non?slip pad at the button, sturdy and durable, a good computer volume control knob for watching videos, playing games, etc. specification:Item Type: USB Volume Control Knob Material: Aluminum alloy Cable Length: Approx. 2meters / 6.6ft PackageList:1 x USB Volume Control Knob 1 x USB Cable 1 x User Manual