Industrial Flap Discs Long working life. These flap discs are made with unique abrasive cloth that RAF exclusively designed and produced for these discs. This range exhibits high temperature and pressure resistance, resulting in a disc offering exceptional long working life. It is ideally suited, at medium-high working pressure, for any steel and metal work, as well as, in foundry applications. The discs are all iron, sulfur and chlorine free (<0.1% Fe, S, Cl).