Norton Bench and Pedestal Grinding Wheel, Straight, Series: 39C, 12 in Wheel Dia, 2 in Wheel Thickness, 1-1/2 in Center Hole, 60 Grit, Medium Grade, Silicon Carbide Abrasive, 2070 rpm Maximum, Vitrified Bond, Green Wheel, Applicable Materials: 300 Series Stainless, Titanium, Aluminum, Brass, Bronze, Copper, Gray Iron, Masonry and Natural Stone, Wheel Type Number: Type 1, Wheel Hardness: K