Round Damper, 16", with 24-volt, spring return Damper motor used to control volume of circulating Air in heating, cooling, and Ventilating systems. Galvanized steel, single-blade Damper. Shipped as power closed/spring return open Damper, for use with Honeywell Zoning Systems. Can be field-converted to power open/spring return closed Damper when used as an independent zone or for Fresh Air intake. Blade closes off tightly against gasket for minimal leakage. Rated to operate up to 1" water column (wc).