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. Works With Heating ducts, Control Type Manual/automatic, Dimensions L x W x H in. 6 in. Diameter, Includes 1 Booster fan, Material Type Metal w/plastic blade, Motor 30 W motor, Mount Type Hardwired or wire to an on/off switch special order, CFM 180.