The film backing gives you a close-tolerance, consistent finish, making it a good choice for applications such as spot repairs, sanding plastic parts, paint feathering on defects, or sanding automotive primer. To help reduce loading on the disc, we designed an open coat construction without a load-resistant stearate coating. Our convenient 3M™ Hookit™ hook-and-loop attachment on the backing enables easy re-use so the disc can be used again and again for the life of the product, and attaches to our low-profile 3M™ Hookit™ Disc Pad (sold separately) on a random orbital sander. Our Film Disc 360L comes in a range of grades for various applications from fine sanding to finishing. 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 in grinding applications in addition to sanding and finishing applications. Aluminum oxide is suitable for a wide variety of materials in both woodworking and metalworking, including ferrous alloys. At 3M we offer a complete line of hook-and-loop style 3M™ Hookit™ discs for work spaces where adhesive backed discs may become contaminated by dust, dirt, or flying debris. They are often used in applications where a 3M™ Stikit™ disc may be too aggressive, as Hookit™ discs tend to leave finer finishes than adhesive backed discs. Hookit sanding discs conveniently and firmly attach to a hook-and-loop backup disc pad (sold separately) on a random orbital sander, can be removed cleanly and easily, and can be re-used again and again for the extent of the abrasive life