Polyken/Nashua 438X Extreme Weather FSK Tape is a Foil, Scrim, Kraft laminate tape with acrylic adhesive suitable for use in a wide range of temperatures. Used to seal and patch FSK duct boards and insulation. Provides an extra-strength seal to maintain vapor barrier integrity. Polyken/Nashua 438X is specially designed to meet high strength, tear resistant sealing tape requirements. Provides excellent adhesion to substrates over extreme temperature ranges (from -35DF to 260DF). Diamond patter matches most FSK boards and blankets. Complies with low VOC (Volatile Organic Compounds) requirements of SCAQMD Rule 1168 and contributes toward satisfying EA Credit 1 (Optimize Energy Performance) and EQ Credit 4.1 (Low Emitting Materials, Adhesives & Sealants) under LEED. Comes on a paper release liner.