2 dual-sided whetstones: 400/1000 grit and 3000/8000 grit for ultimate control; stones use water (vs. oil) for sharpening; clean easily with water Knife-sharpening angle guide: helps maintain a correct angle and consistent pressure when sharpening a blade Non-slip design: silicone base holds stone inside and non-slip bamboo base keeps unit securely in place for added safety while in use Flattening stone: for easy stone maintenance―quickly returns the stone’s surface back to its smooth, original flatness Versatile and warranty: sharpens a wide range of knives and other cutting tools, including kitchen knives, scissors, pocket knives, hunting knives, and more; backed by an Amazon Basics 1-year limited warranty