KALEFANS adopts U.S. technology and specializes in the production of HVLS ((High Volume - Low Speed) draught fan, an extra large energy-efficient fan with maximum diameter of up to 7.3 meters. The Kale Airfoil Blades � streamlined blades manufactured with the application of aerodynamic principles and advanced technology could use only 1.5KW or less power to drive a mass of air, resulting in large areas of natural wind systems, to play a dual function of ventilation and cooling. It can be called as a perfect solution for ventilation and cooling in large and high space.