Z-Flex Z-Vent 4" Termination Hood with Damper Stainless Steel Venting (2SVSHTD04) 4" Termination Hood with Damper Stainless Steel Venting Last piece in a horizontal venting system if you want to exhaust out the side wall. Ideally suited for homes with aluminum or plastic siding Has a damper and therefore cannot be used as an intake vent hood