The series of fans have following characteristics: low investment, significant ventilation and cooling effect, low noise, big air volume, small energy, smooth operation and long life, high efficiency and so on. They can be used in poultry houses, greenhouses, factory workshops, supermarkets, dining houses, stadiums and etc. they are the best cooling equipments in the large size places of the times. The shutter adopts automatic controlling equipments to let shutter blade automatically open and close by 90 degrees, thus it can reach the purpose of dustproof waterproof and effect of perfect. The quality of the products has reached the international standard. Information of one of our main fans below is given now for your reference: commodity description: Air capacity: 43170 m3/h Size: 1380í-1380í-450mm Noise: í_64dB Power: 1.1kw Voltage: 380V Electric current: 2.8A Weight: 88kg Material: Frame: galvanized steel sheet, the layer of the galvanization is 180g/¬Oú¼and the frame is one-off molded, also there is a outlet in the bottom. Fan Blades: 6 pieces of mirror face stainless steel blades with the diameter of 1270mm and the angle of the blades is patented designed. The fan translations have all passed the experiment of homeostasis, which makes the air volume keep the same as the very beginning during the operational life span of the fans. Shutter: high strength hot-galvanized steel sheet, with a centrifugal system which can ensure the shutter opens with the angle of 90 degrees under all the conditions. And uncontrollable air can never goes into the birdhouse as the shutter works. Belt Pulley: the V type belt pulley is aluminum magnesium alloy injection molded, so ití»s light and high-strength. Belt: the belt is imported from Japan it is ametabolic in a longtime. Motor: The motor is high efficiency and low wastage of energy and have accredited 3C certification; the Grade of Protection is IP55 and the Insulation Grade is F. Maintenance free: there is no use to maintain it during its life circle. Performance: it is used to ensure the minimum and transverse ventilation in spring and fall and it usually works with the air inlet.