The Mastercraft 9 x 11” Sandpaper Set with 5 Pieces is manufactured for general-purpose sanding and is ideal for use on hardwoods, metal, and fibreglass. The durable sanding sheets in this kit provide a variety of grits, all of which can make a solid choice for the removal of stock, surface coatings, and rust. The sheets all feature an aluminum oxide abrasive to ensure that any sanding or polishing tasks you take on are completed both quickly and easily. These Mastercraft sandpaper sheets will fit easily onto most electric sanders and polishers, even those from other brands, so you can set them up and get to work in seconds. Finally, the sandpaper is made from durable synthetic material with self-renewing properties that allow the surface to break down under the heat and pressure of continuous sanding to create new sharp edges, extending their overall tool life.