... air volume, without distortion, no broken, attractive and durable.( adopting aluminum fan blade in the past, which had some problems caused by ... sizes of shape and install conveniently.5) Size of shape(blade): 780mm*780mm*420mm(27”),830mm*830mm*400mm(30”),900mm*900mm ... fan work smoothly:Adopt the Aluminum Magnesium Alloy pulley and blade impeller:Fanblades in Stainless Steel,no broken,long service life ...