Some great features of this product include:
Round Damper, Automatic, Dia 6 In, Voltage 24 AC, Height 7 1/2 In, Output Amps 6 VA, Connection 2 Wires, Application Controls Air Flow In Heating And Cooling Systems, For Use With HZ432, HZ432K, HZ322, HZ322K, HZ311, HZ311K, W8835A1004, Y885A KITS Control and Static Pressure DampersRoundFresh AirWith 24VAC power open/spring return closed motor. Connect to any rigid or flexible round duct. For ventilation fresh-air intake or combustion makeup air. 2-wire connection.
Buy for $98.83 brand new