... 2)large air output Take 54’’ type of fan for example,the measured air volume of better quality ... ,and it can work steady. 4)long lifetimeThe fan casing and motor stents were produced by the material ... is PVC,also resist corrision and air-slake. Fan blade is made of nylong and fiber material,have ... 5) Low failure rateBecause of the electric motor and fan blade connected directly ,it has no belts,belt pulley ...