3M Flap discs offer an unbeatable system for grinding and blending in one easy step. The construction wears away, exposing fresh mineral to extend disc life and provide consistent cut rates. Great for weld grinding, blending, deburring, rust removal, surface prep and edge grinding on all types of metals. - 3M 747D Ceramic grain abrasive flap disc constructed on a X-weight, durable cloth backing. Resin bonded for heat resistance. Straight shaft spindle mount for easy attachment.