200 grit (red) = Course. Best for sharpening & removing larger burrs. This stone will sharpen your edges without using a file first! These are the best diamond stones on the market. It's a good idea to carry in your pocket for a quick hand sharpen or remove a burr.400 grit (orange) = Medium. A good in between stone for sharpening, carrying in your pocket on the hill & finishing.600 grit (violet) = Very Fine. Best for polishing & finishing. For best performance all diamond files can be used with either water or cutting oil for optimum sharpening & polishing characteristics. All stones come with high quality, non flexible, flat (important) aluminum backing plate that is colour anodized & laser-etched. Many WC service techs prefer these. Replacement diamond strips can easily be removed & replaced to save you money!