Flextape (5e Equipment)
From D&D Wiki
Flex Tape (R)! The super-strong waterproof tape! That can instantly patch, bond, seal, and repair! Flex tape is no ordinary tape; its triple thick adhesive virtually welds itself to the surface, instantly stopping the toughest leaks. It even works underwater! Small size 4" by 5', medium size: 8" by 5', large: 12" by 10'