What It Is: Dior Base Vernis is a strengthening and hardening nail polish base to apply to the nail surface to prepare it for applying polish and maximize wear. What It Does: To prepare for nail polish application and optimize its wear, Dior has created Dior Base Vernis, a protective nail care base that strengthens and hardens nails. Its ideally smooth texture ensures the manicure's perfect finish. How to Use: Apply a coat of Dior Base Vernis before applying your nail polish to optimize manicure results. 0.3-oz.