240 Volt/ 50-60 Hz, Through-Wall Utility Fan. With 90 CFM, 3.5 Sones, 1 Amps, 6” duct. Can be installed in outside walls from 5-1/4 to 10” thick (wall with less than 6” thick will not use the 6” diameter flexible duct). 6” Diameter Flexible duct included.