Thermaltake’s Mobilefan II is a perfect cooling accessory for Notebooks and Desktops. It is powered by USB and features a cable box to retract the USB cable. The 80mm fan moves up to 47 cubic feet per minute (CFM) of airflow at a low noise level - more than enough to prevent you from sweating or cool down the hottest part of your laptop. Features a one-touch retractable USB power cable box for quick packaging and draws power directly from the USB port of your desktop PC or laptop, so you don’t need to take additional power adapter wherever you go. A VR knob allows you to manually adjust the fan speed according to your need.