3M Cubitron II Hookit Film Disc 775L, 120+, 5 in x NH, Die 500X, 50 per inner, 250 per case. 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.
eBay