Supco DB8--DUCT BOOSTER 8"Duct Boosters are used to increase air flow in both hot and cold forced air systems, the DB series provides the easy, economical solution.Features/Benefits:Dimensions: 8" (DIA) x 8"Fan Blade Diameter: 7"RPM: 1750CFM: 500Easy InstallationEnergy savingsFits in round, square orb rectangular ductsOperates only when you want itWatts: 60Amperage: 0.75Operating Voltage: 115Undersized heating & cooling equipment. Low air flow areas.