This 10-pack of Power Pro #220 Grit Hook and Loop Perforated Drywall Sanding Discs attach to the Power Pro Series drywall sanders for use with hook and loop discs. The hook and loop (Velcro) system allows for quicker, easier disc changing and the #80 grit discs will the most useful on the initial drywall compound application and tougher material. For smoothing surfaces and removing small imperfections, use 80- to 120-grit sandpaper. For finishing surfaces smoothly, use a fine sandpaper with 150- to 220-grit. Many jobs require you to “go through the grits.” This means you start the project using lower-grade grit and use finer pieces of sandpaper as you progress. Each time you advance to a higher grit sandpaper, you remove the scratches from the previous layer.