... .95Hardness 2150 Knoop scaleMagnetic Material 0.0025%Grain Sizes Available (F):12, 14, 16, 20, 22, 24, 30, 36, 40, 46 ... , 120, 150, 180, 220.Microgrit Sizes Available (F):240, 280, 320, 360, 400, 500, 600, 800, 1000, 1200. Grain Size Distribution :Upon ANSI B74 ...