3M™ Scotchrap™ Tapes 50 and 51 are tough, polyvinyl chloride based tapes with special high tack adhesives formulated to resist corrosion of metal piping systems above and below ground, fittings and joints on all mill-coated pipe and electrical conduit systems. These tapes are: Resistant to salt water, soil acids, alkalies and salts, common chemicals, chemical vapors, and exposure to outdoor weathering and sunlight. Resistant to impact, abrasions, punctures, and tears. Tape 51 provides similar qualities in a thicker, 20 mil (0.508 mm) tape, Both tapes electrical insulating properties.Information provided by 3M |