Norton Gemini Bench and Pedestal Grinding Wheel, Straight, Series: 57A Alundum, 8 in Wheel Dia, 3/4 in Wheel Thickness, 1 in Center Hole, 100/120 Grit, Fine Grade, Aluminum Oxide Abrasive, 3600 rpm Maximum, Vitrified Bond, Brown Wheel, Applicable Materials: 300/400 Series Stainless, Hard/Soft Carbon Steel, Tool Steel, Titanium, Superalloy, Aluminum, Brass, Bronze, Copper, Cast Iron, Ductile Iron and Gray Iron, Wheel Type Number: Type 1