Flap Disc are created by overlapping coated abrasive flaps and adhering them firmly to a back-up plate,This design provides a cooler running,longer lasting disc.And because new layers of abrasive are constantly being exposed,a very consistent finish is provided during the life of the disc.These discs are specifically recommended for high stock removal on stainless steel,carbon steel,aluminium,and most alloys.They offer many times the life of conventional resin fiber discs