The Blue side is suitable for general carpentry tools, tinsnips, side cutters, wood bits, garden tools etc.
The Black is suitable for damaged woodworking tools, cold chisels, axes, lawn edgers etc.
Black: Extra Coarse 220g, 60 micron
Blue: Coarse 325g, 45 micron
W10 Double sided (combination) diamond whetstones will not break, chip, crack, hollow or groove. These ultra precision whetstones are lightweight and have a totally rigid construction. 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