Nikwax Map Proof is a sponge-on waterproofing solution for your map. This product repels water from paper, maps and other charts, while maintaining flexibility. Aside from adding water repellency to paper, Nikwax Map Proof prolongs the life and performance of it too! Your maps can also still be written on, even after treatment! How to Apply: Spread evenly over area, then wait for 2 to 3 minutes. Wipe away excess treatment with a cloth and allow to dry completely before folding. Note from Nikwax: Poor quality maps may wrinkle slightly after treatment and can be restored using a cool iron. Bottle is sufficient for 4-5 average size maps.