... noise 3)High technical,energy saving 4)Copper motor automatic poultry equipmentturbo air ventilation fan,ventilator,poultry farming ... 1400B1535*1535*4001.5Hammer style9FJ-900B1000*1000*4000.55shutter, frame, wind set aregalvanized, blade is stainlesssteel 9FJ-1000B1100* ... *1535*4001.5Push/pull style9FJ-900B1000*1000*4000.55shutter, frame, wind set , fan blade aregalvanized9FJ-1000B1100*1100*4000 ...