This Explosion Proof Direct Drive Fan withstands environments with explosive gases. Ideal for duct applications in mills, mines, foundries, factories and more. Exhaust axial fan helps remove fumes, dust, smoke or steam from poorly ventilated areas. Drum housing is made of heavy gauge all welded steel. Fan blades are made of non-sparking cast aluminum and are powered by an explosion proof motor to handle environments with explosive gases present. Drum features angle iron flanges welded on each end. Angle flanges are pre-drilled with eight 7/16" diameter holes around the bolt circle for easy mounting. Three phase design. Horsepower rating based upon maximum speed/load.