Helps to break the nail-biting and thumb-sucking habits, and offers prevention treatment with an easy, brush-on application. Works by using a combination of a bitter, yet harmless, taste and a clear enamel. Keeps nails healthy and strong, and keeps hands out of the mouth to prevent the spread of germs. Safe for all ages (4+ years). Recommended for adults and children by dentists, orthodontists, and pediatricians.