Pferd Grinding Wheel, Type 27, Series: SG Series, 4-1/2 in Wheel dia, 1/4 in Wheel Thickness, 7/8 in Center Hole, Arbor Connector, A24Q Grit, Ceramic Oxide Abrasive, Wheel Type Number: Type 27, 13300 rpm Maximum, Applicable Materials: Steel and Stainless Steel, Wheel Hardness: Q Pferd 60055 SG Series Type 27 Grinding Wheel, 4-1/2 in dia x 1/4 in Thick, 7/8 in Center Hole, A24Q Grit, Ceramic Oxide Abrasive