Three-stage system provides professional results at home by sharpening kitchen and sports knives quickly and easily. Adjustable blade selector provides optimum sharpening angles. The blade selector adjusts the guides to the perfect angle needed for precision sharpening. Select thick for hunting knives, medium for chef's knives and standard kitchen knives, and thin for light blades like fillet or paring knives. Simply draw the knife through each slot a few times to achieve a razor-sharp edge. Stage 1 begins the sharpening process with a Sapphirite coarse-grinding wheel to create the proper angle. Stage 2 continues sharpening with a Sapphirite medium-grinding wheel giving the blade a precise edge. Stage 3 completes the process with an extra fine-grit ceramic wheel polishing the blade to an exact, razor-sharp edge.