The 3M 425 Aluminum Foil Tape is a 2.5 mil dead soft aluminum foil backing with an acrylic adhesive. It has a temperature resistance range of -20F to 250F. This tape is used for HVAC duct sealing, joining sheet metal, patching and sealing foil-faced insulation, and wrapping pipes and hoses. It comes in a standard 2 inch x 60 yard roll and has a tensile strength of 35 lbs/in. The 425 tape provides a moisture resistant seal and conforms well to irregular surfaces.