Features: 1. Made of high quality red corundum and green silicon carbide, very comfortable and durable to use. 2. Double sided grindstone design, convenient and easy to sharpen knives. 3. Excellent sharpening performance. 4. The side of 1500 grit can be used to remove burr on the edge of a knife. 5. The side of 400 grit can be used to coarse grind to form an edge or repair badly damaged blades. Specifications: Material: Red Corundum + Green Silicon Carbide Grit Type: 400 Grit & 1500 Grit Size: Approx. 100 x 35 x 22mm / 3.94 x 1.38 x 0.87inch Color: 400 Grit: Rust, 1500 Grit: Mint Weight: Approx. 151g Directions: 1. Soak the stone in water about 15 minutes before using, saltwater is better. 2. Sharpen the knife in the order of the first rough then precise. 3. When you sharpen the knife, hold the handle of the knife with the right hand, left hand fingers are lightly pressed to the edge of the knife, move in a clockwise direction. 4. The sharpening angle is best from 10 to 20 degrees. 5. Do not scrape the slurry off when grind, knife can be ground more sharp with the slurry. Package Include: 1 x Sharpener Stone Note: 1. Monitors are not calibrated same, item color displayed in photos may be showing slightly different from the real object. Please take the real one as standard. 2. Only sharpener stone, no other stuff included.