Three stage sharpening system for professional results at home. Sharpens kitchen and sport knives quickly and easily. More economical than taking Knives in for sharpening. Interchangeable blade guides provide optimum sharpening angles for three different blade types. Thick for hunting and chef's knives, medium for regular kitchen knives, and thin for light blades like fillet and paring knives. No guess sharpening. Blade guides automatically hold knife at the perfect sharpening angle.