Dewalt HP Flap Discs Type 29, 4-1/2-Inch by 5/8-Inch-11 80 GritDesigned for grinding angles of 20 25 degrees, DEWALT Type 29 HP Flap Discs quickly remove material with aggressive grinding action. Featuring zirconia grit, which removes material 3 times fast than fiber resin metal sanding discs, each disc is packed with a premium abrasive cloth that lasts 15 times long than fiber resin metal sanding discs.