Made with premium silicon carbide, the 400-1000 grit green side is suitable for all everyday sharpening, such as repairing large edged knives and knife polishing, the 3000-8000 grit red side will help make knives smoother after using 400-1000 grit. Comes with two 7" x 2.2" x 1.1" whetstones, a quality bamboo base and plastic bases. rubber grips, a flattening stone, an angle guide for beginners and a quick guide with all the right tips for sharpening knives, can also be a great household gift idea. No need of oil, just put the stone in water for 10-15 minutes before using and it's ready to use. You can always add water during sharpening, with water the lubricating effect of sharpening will be great and will help you save strength. One stone, an unlimited number of professional knives. The sharpening stones are compatible with all types of knives, including chef's knives, hunting knives, pocket knives, Japanese knives, butcher's knives, paring knives, barbecue knives, chisels, wood chisels and blades. Also suitable for hatchets, axes, carving and gardening tools. This white corundum wheel is faster to pulp and has strong self-sharpening power. When the white corundum grinding wheel is sharpened, new edges and new corners appear very quickly, and the self-sharpening property is good. Therefore, the dressing of the grinding wheel is not very frequent, and the work efficiency can be improved.