3M 5″ 501C FIBRE GRINDING DISCS – 3M Fibre Discs 501C feature the tough, sharp alumina zirconia (AZ) mineral. Versatile enough to work on a wide variety of metals. Fast cutting, long-lasting and cool running for weld grinding and blending, metal and coatings removal, heavy duty deburring metal finishing. Disc is 5″ x 7/8″. Product is sold by the individual disc.