Product Description 3M Extreme Sealing Tape 4412G is a gray, highly conformable, single-sided, pressure sensitive acrylic adhesive tape with a high performance ionomer backing. It is an ideal solution for creating a water tight seal. It conforms over fasteners, seams, joints, holes and gaps to ensure a long-lasting seal on a variety of substrates. From the Manufacturer 3M Extreme Sealing Tape 4412G is an ideal solution for "roof-to-trim" sealing and sealing around roof top mechanical fasteners on commercial vehicles, eliminating the need for large quantities of liquid sealants. It is very tacky and meets the need for a wide variety of difficult sealing applications. As a single coated tape, the sealing is generally done by "oversealing" an existing joint or penetration, as opposed to "between surface sealing" applications typically done with a double coated tape, gasket, or liquid sealant/adhesive. The acrylic adhesive used in 3M Extreme Sealing Tape is manufactured from the same technology platform as 3M VHB Tapes.This pressure sensitive adhesive tape offers exceptional performance for difficult sealing applications. The ionomer film backing is very tough yet flexible and abrasion resistant. It is conformable for creating an effective seal over contours, edges rivets and screw heads. The thick acrylic adhesive is very soft and has excellent sealing properties along with good outdoor durability. It is designed bond strongly to the ionomer film so that overlapping tape joints can be made while maintaining a strong, effective seal.What are Ionomers?Ionomers are comprised of any class of polymer materials consisting of thermoplastic resins stabilized by ionic cross-linkages. Some commercial applications for ionomers are golf ball covers, semipermeable membranes, sealing tape and thermoplastic elastomers.