Flex Seal Flood Protection Tape is designed to help prevent damaging flood waters from entering people's homes and businesses. Should be used on smooth, even, flat surfaces and always in combination with our other Flood Protection products. Instantly bonds to horizontal and vertical surfaces. Use on all types of openings such as windows, doors, seams, garages, casings, thresholds, conduits, vents and ducts, key holes and more. No water penetration through 1/2 In. gaps at depths up to 3 Ft. for 14 days.