CND Shellac Wear Extender Base Coat offers 3 weeks wear and extends the wear of gel polish while smoothing imperfections and ridges when used as directed. Shellac Wear Extender Base Coat creates an even nail surface for easy application while improving the nail appearance. Easy 10-minute removal when used with Xpress top coat. Features a new curve hugging brush that have 200 bristles that adapt to the nail for better coverage and application.