The 0800 Collection is offered in two frame styles to be used with steel duct: a double flange screw hole mounting type (M1) or simply a knock-about tab variety (M2). The two styles have an easy set up Minimize-out template which makes the oval condition openings added straightforward to Slice. https://dampersforindustrialsecto35566.ttblogs.com/16742798/dampers-for-industrial-sector-options