"Fans boost air flow in hard to heat or cool rooms. Install easily in both metal and flex round duct. 6in. fan with 120 Volt, 30 Watt motor moves 180 CFM through 25ft. of straight duct. U.S.A. Control Type Manual/automatic, Motor 30 W motor, CFM 180, Material Type Metal w/plastic blade, Works With Heating ducts, Mount Type Hardwired or wire to an on/off switch special order, Includes 1 Booster fan, Dimensions L x W x H in. 6 in. Diameter."