Versions 0110DOW, 0120DOW, 0110GOW and 0120GOW are "from wall or floor" integral sleeve static curtain variety fire dampers.  Design 0110GOW and 0120GOW are specifically created for supply or return ducts that terminate at a grille or sign-up. Design 0110DOW and 0120DOW are created for by means of penetrations (ductwork linked https://dampersforindustrialsecto13445.therainblog.com/35853861/helping-the-others-realize-the-advantages-of-heavy-duty-stainless-steel-damper-manufacturers