Selkirk DSP7DK-1 Stove Pipe Damper Kit, 7"Highlights: Size: 7" Diameter Allows the operator to alter the amount of air drawn through the venting system, controlling the stoves combustion Must be installed directly on the stoves flue outlet When handle is in horizontal position, the damper is closed (reducing combustion) The closed position is still 20% open, so the venting system is not completely blocked When handle is in vertical position, the damper is wide open (no reduction of combustion)