Lansky Deluxe 4 Stone Diamond Knife Sharpening System - For knife enthusiasts, you might want to invest in one Extra Fine or Supper Sapphire ceramic hone to polish your blade to a mirror finish and a serrated hone to truly complete your ultimate kit. The ultimate in knife sharpening systems technology. It is safe, easy and convenient to use. The Lansky Controlled-Angle Sharpening System is designed to give your blade a professional, razor sharp edge every time. Included Stones: Extra Coarse Diamond (70 grit)Coarse Diamond (120 grit)Medium Diamond (280 grit)Fine Diamond (600 grit)