Thick, Solid and Large Whetstone: Made of professional grade white corundum, perfect for the larger chef's knives, gives a nice working area for any size of knife, corrosion-resistant, heat-resistant, edges and corners are clearly demarcated 2 Grit Sides Ensure Best Sharpening: 400 grit side has good metal removal rate, light scratches edge. Intermediate stage before finer grits. 1000 grit side leaves metal edge with frosted appearance. Edge sharpness equivalent to majority of factory edges on knives, tools. Suitable for Most Grinding Operations: Kitchen knives, hunting knives, kitchen shears, pocket knife, chef knife, porting knives, straight razor, cutting class knife grinding, precision tool, garden tools, art appliance and ceramic knife, but serrated blades and ceramic knife etc Safety Guarantee with Silicone Mat: The non-slip silicone base keeps the stone firmly in place, amazing experience without moving at all 1000 Grit Side: This grit is a very good overall grit. It is fine enough for many jobs and still have enough abrasive properties to do sharpen knives and tools that are not very dull. If you keep your knives and tools in good shape, you'll find yourself reaching for this grit level often. This grit is also very common for the final stage for many kitchen knives. 400 Grit Side: Instructions to use: 1. Soak the sharpening stone with Water for 5 minutes, then put it on a steady surface such as a table or a desk. 2. First use the #1000 grit side for coarse grinding in 10~30 degree angle, push the knife out with a little force, and then gently retracted. This process takes about 15 minutes. Then use the #4000 grit side for fine grinding. This process takes about 10 minutes. 4. After sharpening the knife, clean the knife with wet cloth or Water, then dry it. 5. Use a soft brush to clean the sharpening stone, then placed in a ventilated place out to dry. Material: White Corundum Color: Light Green+White Dimension: 18*6*3cm, 7.09 inch(L) x 2.36 inch(W)x 1.18 inch(T) Weight: 19.75oz./pcs Packing List: 2 x Sharpening stone 1000/400 Grit 2 x base holder Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Sharpening Stone sharpening tools Dual Grit Sharpening Stone