This Duct Fan is designed for moving air with high moisture content. Great for spray booths, ducts and industrial washing machines. Fan blades are made of non-sparking cast aluminum. Axial fan features a totally enclosed motor. Housing is made of heavy gauge steel with angle iron flanges welded on each end for superior strength. Sealed ball bearings have external grease fittings. Bearings are located in the belt tube, removed from contaminated airstream. Belt tube interior is protected from contaminated air in duct by water slinger, dust cover and shaft seals. Angle flanges are pre-drilled with eight 7/16" diameter holes around the bolt circle for easy mounting. Adjustable motor base provides proper belt tension. Cast steel and turned steel sheaves. Continuous weld design is moisture tight. Three phase design. Horsepower rating based upon maximum speed/load.