Product D0110DOW, D0120DOW, D0110GOW, D0120GOW are "out of wall or ground" integral sleeve dynamic curtain sort fireplace dampers. Design D0110GOW and D0120GOW are designed for source or return ducts that terminate at a grille or sign-up. Product D0110DOW and D0120DOW are created for via penetrations (ductwork linked to either side) the https://heavydutystainlesssteelda34556.spintheblog.com/37483318/dampers-for-industrial-sector-an-overview