Airmaster 42711 High Pressure Belt Drive Fan, Single Speed, Totally Enclosed, 3 Phase, 36" Prop Diameter, 230/460V, 1HP Motor 1-speed 36" belt-drive exhaust fan for use in exterior ventilation 230/460V, three phase, 1 hp, permanently lubricated, totally enclosed ball bearing motor 12,475 cubic feet per minute (CFM) airflow rate Four aluminum blades with permanently lubricated bearings on blade drive shaft UL Listed for quality assurance