Naniwa Diamond Abrasive Sharpening Stone offered by us is a simple, long-used tool that grinds blades against an abrasive surface to sharpen them. This sharpening stone is composed of a variety of natural and synthetic materials with varying degrees of abrasion. This stone is very easy to install and simple to use. Naniwa Diamond Abrasive Sharpening Stone is designed to be utilized in the preparation of surfaces for final polishing after machining or spark eroding. This stone is very effective as well as economical and safe to use.