Centrifugal Downblast Roof Exhaust Fan, Drive Type Belt Drive, Assembly Unassembled, Wheel Diameter 18 1/2 in, Base Diameter Not Applicable, Base Length 30 in, Base Width 30 in, Base Shape Square, Nameplate Voltage 230/460V AC, Phase 3, Motor Horsepower 1/3 hp, Exhaust Airflow @ 0.000 in SP 3, 150 cfm, For High-Static Pressure Applications No, High-Efficiency Motor No, For Air Type Flammable Vapor, Includes Drive Package Yes, Includes Motor Yes, Mounting Location Roof