Styles 0110DOW, 0120DOW, 0110GOW and 0120GOW are "from wall or floor" integral sleeve static curtain style hearth dampers.  Model 0110GOW and 0120GOW are particularly designed for supply or return ducts that terminate in a grille or sign-up. Model 0110DOW and 0120DOW are suitable for by way of penetrations (ductwork connected https://heavy-duty-stainless-stee13456.therainblog.com/35700992/everything-about-dampers-for-industrial-sector