Made with superior silicon carbide, the 400 grit side is suitable for any daily sharpening, such as repairing the knives with big cutting edges, and polishing the knives, the 1000 grit will help you to make the knives more smooth after 400.
No oil is needed, just put the stone into the water for 10-15 minutes before using and they are ready to use. You can always add water to it while sharpening, with water the lubricating effect of grinding will be great and helps you to save strength.
This grindstone made of white corundum is quicker in pulping and high in self-sharpening. When the white corundum grindstone is ground, the new edges and corners will come up very fast, and the self-sharpening property is good.