Hessaire shutter exhaust fans are built to industrial application standards with corrosion resistant extruded aluminum frames which will not rust on any mounted surface even when exposed to the harshest elements. Hessaire shutter exhaust fans are ideal for exhausting heat, fumes, and odor in residential, commercial, industrial and agricultural buildings. Hessaire offers shutter mounted exhaust fans from 8 in. to 36 in. to fit any size opening. 1.5 in. W flanges on the shutters make the unit easy to install. Louvers are constructed with light aircraft grade aluminum alloy for minimal air resistance. Prop is constructed with 5052 aluminum alloy engineered to precise geometry for quietness and air-moving efficiency (except for 30 in. and 36 in.- grade G90 galvanized for maximum rust protection). The felt lined edge on louvers provides quiet closing and superior weather seal. Hessaire achieves the best in class efficiency measured in CFM/Watt. Hessaire is a trusted name in air-movement engineering. Color: Silver.