Paint Prep and Defect Repair Our 3M Paper Sheet 210N is best suited for hand sanding and finishing due to its exceptional conformability and fast cutting abrasive material. Its A-weight paper backing can be easily cut and folded to fit any work piece or hand tool, and distinct brown color to easily differentiate it from other grits and grains.** Fast-Cutting and Durable Aluminum Oxide Aluminum oxide is a popular choice among industrial professionals because of its fast cut-rate and long life. This mineral makes a tough, durable abrasive that self-fractures to expose fresh cutting edges, whereas traditional natural abrasives dull more quickly. Due to its fast cut-rate, hardness, and strength, it is widely used for sanding and finishing applications. Aluminum oxide is suitable for use on a wide variety of materials in woodworking.** Open Coat Resists Loading Sanding paper cuts better and lasts longer when dust isnâ€™t clogging the cutting surface of the abrasives. Open coat construction means the abrasive grains are placed with space between them to help evacuate sawdust and other sanding debris and avoid clogging the cutting edge of the grains. This allows the sheet to continue cutting even when sanding softwoods, paints, and other materials that would, otherwise, clog the grain and hinder sanding ability. Additionally, the open coat feature provides a more aggressive cut than a comparable closed coat abrasive of the same grade.All of this adds up to increased productivity and reduced material consumption.