Transformer Cooling Fan Blade Diameter 20 in Air Flow 6 600 cfm Voltage 115/230V AC 60 Hz Phase 1 Fan Mounting Type Guard Mount 4.1/2.1 Amps 1 725 RPM RPM Motor HP 1/2 hp Max Ambient Temp 104 Degrees F Bearing Type Ball Number of Blades 4 Blade Material Cast Aluminum Fan Cord Length 15 ft Guard Material Steel 23 in Height Width 23 in 13 5/16 in Depth Mounting Eye O.C. 17 3/4 in Motor Enclosure Totally Enclosed Air-Over Motor Insulation Class B Frame 48Y Yoke Mount