Air Duct Insulated Flex-Vent – Model KM 4.2Thermaflex® KM Series KM 9X25FT Flexible Duct, 9 in, 25 ft L, -0.5 to 10 in-WG, Polyester Film/Steel WireDescriptionThermaflex® Flexible Duct, KM Series, Round Vent Duct, 25 ft Length, -0.5 to 10 in-WG, Polyester Film/Steel Wire, 9 in, Additional Information: Fiberglass Insulation
Product OverviewStrong polyester film laminated and encapsulating a heavy, corrosion-resistant steel wire helix, forms the inner core and supports a thick blanket of fiberglass insulation. The outer vapor barrier is a new bi-directional reinforced metallized vapor barrier which will not unravel. The smooth air-tight inner core of polyester is designed for low to medium pressure systems.