Industrial Cased Axial Extractor Fan Air Blower Fan 8/10/12/16/18/20/22/24 inch. 100% Brand New and High Quality! The exhaust fan is made of high-quality metal steel material, is not easy to be deformed, has excellent workmanship, durable frame and long service life. The ventilation fan has high ventilation efficiency and very low noise during operation.Easy to use and maintain. Perfect for exhaust ventilation from home, bathroom, toilet, kitchen, Garage, workshops, basements, attics etc. Without speed control type:(the red line is the live wire L and the yellow line is the zero wire N) With speed control type:(the brown line is the live wire L and the blue line is the zero wire N).