Trend DWS/W8/FC 8-Inch by 3-Inch Diamond Whetstone Double-sided Precision Continual Monocrystalline Diamond Whetstone Fine 1000 grit (15 micron) and coarse 300 grit (50 micron) double side stone Precision flatness of +/- 0.0005-Inch and monocrystalline diamond bonded by electroplating in nickel to a precision ground steel base allows for industrial sharpening of planer knives, shaper knives and carbide tooling Trend continuous diamond stones have 50-percent more diamond compared to perforated holed matrix diamond and continuous diamond surface prevents "snagging" when sharpening small or pointed tooling Used extensively for woodworking, engineering, gardening, catering, outdoor pursuits and in domestic applications Trend lapping fluid is strongly recommended to prevent rusting, clogging and corrosion