SP-650 Stone Grader\n\nChange the grit size on your grindstone\n\n--Adjust the grit of your grindstone to an equivalent of between 220 and 1000 grit.\n--Works with your original grindstone as well as the SB-250 Blackstone Silicon.\n--The fine side can be used to clean your Japanese Waterstone.\n--Easy to use, just press against the grindstone.\n--Works with the Tormek T-8, Tormek T-4 and older models.\nFine sharpening or high material removal\n\nThe SP-650 Stone Grader allows you to adjust the characteristics of the grindstone so that they're equivalent to between 220 and 1000 grit. If you want to adjust the stone for finer sharpening, press the fine side of the SP-650 Stone Grader against the surface of the grindstone with the machine running. This will change the surface of the grindstone to give finer sharpening.\nWhen you want to restore the grindstone to give more effective material removal and coarser sharpening, press the coarse side of the stone grader against the grindstone .