Acme Miami Home Industry ABD-8 8" BackDraft Air Flow Dampers Damper opens with air flow and closes when the air flow stops. Spring loaded with positive closure and a rubber gasket. Country of Origin: UKRAINE. Size: 7-13/16"D x 5-11/16"L. Dimensions: 8.25"Lx8.25"Wx8.75"H. Weight: 2 lbs.