For between coats finishing applications. Electrostatically coated with aluminum oxide to stay sharper longer, sand faster, and resist clogging even when sanding latex paint. Uniform grit for consistent finish. 180 grit for between coats surface smoothing, 240 grit for surface smoothing with a finer finish, 320 grit for final finish, and 400 grit for mirror and premium surfaces. Gold paper and color-coded package for easy identification.