3M™ Cubitron™ II Hookit™ Clean Sanding 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.