US Energy Products Reflective SOFT-FRK Duct Wrap is a composite of glass fiber insulation bonded to FRK facing. This item is designed to insulate heating, ventilation, and air conditioning ducts in both residential and commercial settings within a temperature range of 35°F to 250°F. The R-value of this product, which measures 2 inches in thickness, falls between R8 and R10. Each roll measures 25 feet in length and 4 feet in width, with a thickness of 2 3/16 inches.