Diablo's premium 6 in. 40-Grit (Ultra Coarse) Random Orbital Sanding Discs with StickFast backing include break-through innovations that improve performance, extend sanding life and increase productivity. Featuring a premium ceramic blend, these discs remove material faster than other sanding discs and offer an extra long sanding life. Clog-SHIELD, Diablo's own blend of grinding agents, reduces loading thus maximizing productivity. The superior grain bonding system, ENDURA-BOND, provides Diablo's sanding discs with longer life and extreme durability.