4" Diamond Whetstone™ sharpener with 1" continuous diamond area specially designed with a machinist in mind! Versatile, lightweight and compact pocket model can be used to sharpen, hone or file any hard material. Coarse diamond (45 micron / 325 mesh) to quickly restore a neglected edge. Sharpening with diamonds is fast and easy. No messy oils needed—sharpen dry or with water. Durable construction will provide years of consistent performance and reliable service For proper tool maintenance, woodworkers, chefs and other professionals rely on the superior quality and versatility of DMT® products. Made in USA.