DMT CDT62 6-in-1 Multi-Purpose Diamond and Ceramic Triangle Sharpener 6 in 1 sharpener with 3 flat surfaces in ceramic, fine diamond and coarse diamond plus 3 different radii in ceramic good for flat or serrated edges Versatile hand sharpener for home and shop use Sharpens knives faster than conventional stones with DMT's monocrystalline diamond surface No oil is needed-sharpen dry Durable construction will provide years of consistent performance and reliable service