A nail hardener that not only forms a protective barrier but also prevents chipping, flaking, and splitting of nails. Shake before use, apply only to clean and dry nails. This product is designed to be used once a week. Note that, as with any cosmetic product, overuse can cause unwanted side effects. As your nails get stronger from week to week, you can gradually cover the entire nail. This is especially important if you have very thin or brittle nails.