CGW Toolroom Wheel, 4/3 in Wheel Dia, 1-1/2 in Wheel Thickness, 1-1/4 in Center Hole, 46, Grade: Medium, Ceramic Alumina Abrasive, Wheel Type Number: Type 11, 6685 rpm Maximum, I Wheel Hardness, Vitrified Bond, Applicable Materials: Hastalloy, Iconel, Stellite, Waspalloy, Hardened Tool Steel and Sprayed Metal Coating, Cup Wheel Shape.