CGW Coated Abrasive Flap Disc, Contaminant-Free Economy XL, 4-1/2 in Disc Dia, 7/8 in Center Hole, 36 Grit, Medium Grade, Zirconia Alumina Abrasive, Type 27/Depressed Center Flat Disc, Cotton/Heat Treated Poly Backing, 13300 rpm Maximum, Blue