3M™ Cubitron™ II Hookit™ film disc 775L features 3M™ precision shaped ceramic grain, a revolutionary advancement in abrasive technology. The triangular shaped ceramic mineral is designed to slice through the substrate, rather than gouging or \"plowing\" like conventional abrasives, resulting in a disc that cuts up to 2x as fast and lasts up to 6x as long as conventional abrasives. These discs are ideal for a broad range of applications focused primarily on stock removal and are effective on a wide variety of substrates, including metals, composites, gelcoat and whitewood. The film backing offers greater tear-resistance than paper discs, for additional durability and edge retention. For best results, pair with 3M™ Elite random orbital sanders. 3M™ offers a complete line of hook and loop style 3M™ Hookit™ discs for work spaces where adhesive backed discs may become contaminated by dust or dirt. 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 attach to a hook and loop backup disc pad (sold separately), can be removed cleanly and easily and can be re-used again and again for the extent of the abrasive life. Cubitron™ II 7100145430, Open Coat, Series: 775L, 3 in Diameter Disc, 240+ Grit, Precision Shaped Ceramic Abrasive, Film Backing, 3 mil Backing Weight