Norton, 4-1/2", 40 Grit, Premium Ceramic, Flap Disc, Use On 4-1/2" Angle Grinders, For Use On Wood, Metal, Fiberglass & Painted Surfaces, Premium Ceramic Grains Sands Cooler, Cuts Faster & Lasts Longer, Up To 5 Times Longer Than Traditional Sanding Flap Discs.