http://nexflowair.com/adjustable_spot_cooler_how_they_work.php Compressed air enters at point (A) into the vortex tube component of the spot cooler. The vortex tube splits the compressed air into a hot (B) and cold (C) stream of air. The hot air from the vortex tube is vented to the atmosphere at point (D) after being muffled to reduce noise. Cold air enters into the muffler (E) and is then distributed through the hose distribution kit (F) and onto the item being cooled. A strong magnet (G) holds the spot cooler in place. The temperature of the cold air is controlled by an adjustable knob.