The R4.2 Insulated Flexible Duct is used in standard Heating and Air Conditioning (HVAC) systems and some venting applications. The duct has R4.2 insulation which provides between 2-3% annual savings over standard fiberglass insulation. The product is also covered in a heavy duty, silver jacket for durability. Comes in 25' lengths but it can be cut to length as needed.
