Scotch-Brite(TM) EX3 Deburring Wheel, 10 in x 3 in x 5 in 9S FIN, 1 per case Highest durability wheel for aggressive edge deburring. Convolutely wound on a core. Hard, durable 9 density. Abrasive mineral: Fine grade silicon carbide. Color: Gray MOS: 3600 RPM