This Chef's Choice 1520 Diamond Hone AngleSelect knife sharpener is designed specifically for chefs who need to properly sharpen both modern Asian knives as well as European-style knives. This Chef's Choice sharpener provides both a 15 degree blade angle as well as a 20 degree blade angle in different stages. It's also capable of sharpening serrated, single-bevel, and double-bevel blades. This sharpener from Chef's Choice uses diamond wheels in the first two stages for sharpening even the hardest steel blades.