This USB volume control knob is designed for easily controlling the volume of a computer. Plug and play, with 2m long USB cable and anti-slip mats, it's very convenient to use for watching videos, playing games or more! Features: This USB volume control knob is especially designed for computer, it's compatible with Win 10/ 8/ 7/ Vista/ XP/ Mac systems. USB powered, plug and play, easy to connect to computer, adjusting volume via the rotating knob conveniently. Supports one button mute function, just press the knob once to enter the mute state and press again to restore the sound. Equipped with 2m (6.6ft) long USB cable for more flexible use, suitable for desktop computer or laptop. Made of high quality metal, sturdy and durable. With anti-slip mats in the bottom, stable to use, perfectly fits for watching videos or playing games. Note: Size and color may be slightly different due to manual measurement and different lighting conditions. Thanks for understanding. Specifications: Color: Black Material: Metal Item Size: 65 * 50 * 40mm / 2.56 * 1.97 * 1.57in Item Weight: 150g / 5.28oz Package Size: 13.5 * 9 * 7.5cm / 5.31 * 3.54 * 2.95in Package Weight: 264g / 9.30in Package List: 1 * Volume Control Knob 1 * USB Cable 1 * User Manual (English)