1. Make grinding slurry. Compared with oilstones, it can effectively sharpen knives with less pressure. 2. The double - sided whetstone has a 3000 - grit side for maintenance and fine grinding, and an 8000 - grit side for polishing steel blades. 3. Use water or oil as a lubricant, which is easy to clean. 4. The blue plastic non - slip box with a hinge can be used as a support for the whetstone when sharpening knives. 5. Dimensions: 18 * 6 * 3 cm. 6. Dimensions of the square whetstone: 6 * 3 * 3 cm. 7. The whetstone adopts a double - sided professional grit design, combining the functions of knife sharpening and polishing. 8. Instructions for use: - Soak the whetstone in water for at least 5 - 10 minutes before sharpening the knife. - Insert the knife into the angle guide. - Keep the knife at the right angle and move the blade back and forth on the side of the whetstone. - Alternate the sides of the blade after every one to three strokes of sharpening. - Flip the whetstone to polish the side of the blade. - Test the burrs with paper, not with your fingers. - Clean the whetstone and the knife and store them in a dry place. 9. Colors: White + Green. 10. Material: White corundum. 11. Package contents: - 1 double - sided whetstone. - 1 base support. - 1 square whetstone. 12. Only the above package contents are included, and other items are not included. 13. Note: Light and different monitors may cause slight differences between the color of the item and the actual product. A measurement error of +/- 1 - 3 cm is allowed.