Design 0540V Wide Frame Static Curtain Hearth Damper is UL approved to be used where by creating codes call for the defense of HVAC ductwork penetrations in vertical fire separations (partitions or partitions) which have a fire resistant score of four hours or fewer. The 0540 is assessed for use https://heavydutystainlesssteelda80012.blogrelation.com/43199480/detailed-notes-on-heavy-duty-stainless-steel-damper-manufacturers