Essie Ridge Filling Base Coat
Ridge filling base coat: Give nails with ridges or discoloration a smooth, even base for color application. Leaves nails looking more youthful and smoother, as if resurfaced.
My nails had developed some ridges that ruined the look of a manicure. Smoothing then made them too thin, leading to breakage. Found this and have been a fan for several years now.