Any professional chef will tell you that having properly sharpened knives in your kitchen is crucial. The MasterClass Combination Whetstone is a high-performance all-in-one knife sharpening solution that will hone and sharpen your knives to their precise best. This sharpening stone provides you with complete control over the sharpening process, so you can personalize it to suit your knife. Plus, it's easy to use! The box includes full instructions and a knife sharpening guide to make the process easier for beginners. This sharpening stone is backed by a five-year guarantee, so you can trust that it will last.