rotary wall ventilation fan with big air volume,energy saving, low noise,safe running etc. modelblade diameter(mm)voltage (v)input power(kw)speed(r/min)air volume (m³/min)swaying times(time/min)swaying angle(°)pitch angle(°)GS-400400220/3800.181350120245/9045GS-500500220/3800.251350180245/9045GS-650650220/3800.281350240/260245/9045GS-750750220/3800.31350300245/9045 rotary wall ventilation fan