Recessed Grinding Wheel Type 5 Recess Type One Side Diameter 12 In. Thickness 1-1/2 In. Arbor Hole 5 In. Recess Dia 7-1/2 In. Recess Depth 1/2 In. Abrasive Material Aluminum Oxide Bond Type Vitrified 46 Grit Grade Coarse Hardness Medium (I) Max RPM 2070 Gray Series 32A Specification 32A46-IVBE