Surface Grinding Segment, Color Gray, Abrasive Material Aluminum Oxide, Compatible Chuck ME30777 Cortland, Compatible Tool Type Vertical Spindle Surface Grinder, Grit 30, Overall Length 8 in, Overall Thickness 2 1/4 in, Overall Width 11 1/4 in, Primary Material Applicationn Brass, Bronze, Cast Iron, Steel, Tool Steel, Specification Gemini 30-F, Wheel Type Type 31, Series Gemini 53A, Grade Extra Coarse