The Foil-Grip™ 1402 181BFX is an indoor/outdoor duct sealant that comes on a roll. According to the company, this UL 181-listed, pressure-sensitive duct joint and general-purpose sealant provides an instant water-resistant grip to sheet metal, duct board, flex duct, PVC-coated duct, and duct wrap vapor barriers. Produced with a mill-finish aluminum substrate in conjunction with a butyl adhesive/sealant, it is designed for all applications, including subgrade applications on PVC-coated duct, the manufacturer states.