Design D0110DOW, D0120DOW, D0110GOW, D0120GOW are "away from wall or flooring" integral sleeve dynamic curtain kind hearth dampers. Design D0110GOW and D0120GOW are designed for source or return ducts that terminate at a grille or sign up. Model D0110DOW and D0120DOW are suitable for through penetrations (ductwork connected to either side) https://heavydutystainlesssteelda46778.blog2freedom.com/36924133/helping-the-others-realize-the-advantages-of-dampers-for-industrial-sector