The Lambro 4 in aluminum exhaust wall hood vent with 11 in pipe is ideal for venting through the wall. This vent is used for clothes dryer exhaust, bath fan exhaust and other general venting applications. The exhaust vent allows for maximum exhaust airflow when venting a clothes dryer. The built-in damper prevents back drafts and prevents critters from entering the home through the vent.Maximum exhaust airflow, minimum back pressureFor new or replacement vent installationsOpening and closing damper stays closed when not in use11 in L pipe for through the wall installationAll aluminum designInstallation screws and clamps sold separately