Designed to harden the appearance of your nails, the nails inc. Get Hard Nail Hardener promotes stronger-looking nails in just one week. The formula uses a blend of naturally nourishing ingredients, including biotin, kale, spinach, and mushrooms, to visibly harden and protect your nails. Added retinol enhances the treatment to promote a chip-proof finish. Suitable for brittle, damaged nails. Vegan and certified cruelty-free.