A flap disc is an abrasive disc made of small sheets of overlapping sandpapers arranged in a circular shape. The layered overlapping segments or “flaps” have small grains of abrasives such as aluminum oxide. These abrasive grains are attached to a backing cloth which is normally made from polyester, cotton, or blended material. Flap discs are the ideal choice for a wide range of applications on a variety of metals. Individual flaps break down, exposing fresh mineral to deliver consistent cut rate for the life of the disc. Durable polyester backing material stands up to high unit pressure applications. Designed for use with a right-angle grinder, great for applications where finish is important.