EZE-LAP has been the pioneer in the production of Diamond Sharpeners since the 1970's. EZE-LAP has a patented heat treatment process that bonds the highest quality industrial grade diamond particles in a stainless alloy, to a metal substrate. This process creates a surface that measures around 72 on the Rockwell hardness scale; and results in a Diamond sharpener that will work on high tech blade steels, as well as tool steel, and most ceramic, carbide, and hardened materials. EZE-LAP Fine Grit is a 600 grit diamond sharpener that can handle 98 percent of sharpening needs. The fine grit has sufficient abrasive ability to hone a dull knife: putting a fast razor sharp finish on the edge. EZE-LAP Round Diamond Sharpeners are versatile compact tools for sharpening knives, scissors etc. The Model S is a fine 600 grit diamond sharpener with a 2 ¼" long sharpening area. The D shaped shaft has a groove for sharpening fish hooks, and it stores inside a cap that you can clip onto your shirt pocket.