The O.P.I Nail Treatment Nail Strengthener is a high-quality nail hardener specifically designed to promote the health and strength of natural nails. With a volume of 15 millilitres, this product offers an effective solution for weak and brittle nails. The nail hardener provides protection and helps to safeguard the nails from harmful influences. The formula is free from parabens, making it a gentle choice for nail care. Made in Germany, this nail hardener is part of a comprehensive collection of nail care products aimed at strengthening and protecting nails. The application is simple and can be used alone or as a base under nail polish. The O.P.I Nail Treatment Nail Strengthener is an ideal choice for anyone who values healthy and well-groomed nails.