Roof fan with EC technology. Aerodynamically designed housing made of high-quality polypropylene in grey, diagonal discharge. Operating range from -30 to +80 °C. Integrated guide vanes for optimum efficiency. For horizontal installation. Diagonal impeller made of aluminium, motor-impeller unit dynamically balanced. Electronically commutated DC external rotor motor with ball bearing for continuous operation. High efficiency even in regular operation. Maintenance-free and interference-free. Integrated pressure control for pressure stabilisation during ventilation with optional variable volume flows.