Scotch Foil Tape 3311-10A, 2.0 in x 10 yd (50.8 mm x 9,1 m). Specifically designed to help maintain duct work integrity and optimize HVAC performance. conformable tape with silicone-treated liner that unwinds easily to minimize errors and wasted tape . It is flexible and easy to apply in tight spaces, making it the ideal tape for duct repairs. The soft aluminum foil also conforms to irregular surfaces and provides a reliable vapor barrier.