Our 9-piece set of Sandpaper Discs are designed to fit our ergonomically designed circular hand sanding tool, but can also be used with power sanders that accept circular 3" sandpaper with hook-and-loop backing. The circular design is engineered to deliver an even amount of pressure, thereby reducing divots or over-sanding on a single area. The hook-and-loop backing allows for firm hold when you need it, while still allowing for easy replacement. The aluminum oxide abrasive sanding pad is durable and long-lasting. Use 80 grit for rough wood, 120 grit to 180 grit for general wood, and 240 grit to 320 grit for final finishing of wood, plaster, leather, stone, glass and other surfaces.