Use water for lubrication no oil, smell or mess and can hone ALL hard materials: carbide, steel, the grits are denoted by a dual coloured circle which is set into one end.
Black: Extra Coarse Grade 220, 60 micron
Blue: Coarse Grade 325, 45 micron
Red: Fine Grade 600, 25 micron
Green: Extra Fine Grade 1200, 9 micron
The Red side is suitable for sharpening all woodworking tools, carbide tooling, router bits, 3D bits, woodworking and kitchen knives