Louver-type fans uses CAD/CAM the excellent turning the design manufacturing having the all pressing high, The blower has great capacity the noise is low and circulate steady long ect. In life span characteristics. The automatic open the shutters and close the shutters to attain the dust palliative water tightness, beautiful generous; can immediately blow the breeze, and also can the breeze of take out, is glasshouse factory premises etc. to lower the temperature the well ventilated and the best choice.