Cyclone roof ventilators are powered by the wind to create effective ventilation. It works on the principle of wind assisted ventilation letting the fins rotate creating suction and expelling hot air, humidity, fumes, smoke or dust. Light weight, Durable, non-corrosive design and construction Easily integrated into roofing structures using our soaker-flanges effectively sealing the opening from rain and dust Available in various sizes to accommodate Industrial, Commercial and Domestic needsEco friendly - Economical - Efficient. Cyclones do not require power to operate, they are maintenance free and work full time to extract the hottest air first.