Vermont American 17452 Type 27 Heavy Duty Metal Grinding Wheel , 5/8-Inch Arbor, 4-Inch Wheel, 1/2-Inch Blade Thickness For general applications in concrete, stone and masonry products Silicon carbide grain, 24 grit grain size, in the soft to medium range on the bond hardness scale Depressed center grinding wheel for use with angle grinders Extra strength for high RPM's and withstands lateral pressure