Diablo, 4-1/2", 80 grit, x-lock, flap disc, steel demon grinding & polishing flap discs grind & polish simultaneously to help scale down & smooth out metal & stainless steel surfaces, featuring x-lock, can be changed quickly without the use of tools, a conical shape & 40 grit composition combine for 10x faster material removal, designed to be backwards compatible, these discs work with x-lock angle grinders & 7/8" arbor angle grinders when grinding & polishing metal materials.