The 0800 Collection is available in two body designs to be used with steel duct: a double flange screw gap mounting variety (M1) or possibly a knock-above tab kind (M2). Both styles come with a simple set up Slash-out template which makes the oval condition openings more simple to Slash. https://titussjzon.theobloggers.com/43268963/fascination-about-dampers-for-industrial-sector