Fluorine based, water-repellent glass coating prevents oily deposits and grime from remaining on the window surface. Now, driving in bad weather will be safer than ever. When the coating is set on your window screen, it lasts up to 6 months outdoors, after it has been applied. SENSHA NEPAL Window Crystal improves night vision and wet weather, making visibility up to 10 times clearer. It prevents oxidation (yellowing of the surface) and allows for better clarity during rain. Regular use on car windows will help to continuously retain the water-repellent condition.