Proprietary Austrian-made tungsten carbide sharpener automatically adjusts blade angle (12-20 degrees). This super-hard tungsten carbide sharpener can cut bevels at the angle of your choice. Pull the tip down to cut the factory bevel and up to smooth and align edges without removing metal. Press lightly to get a thin blade for slicing blades. Press hard for a sturdy chopping blade. Triple-action knife sharpener keeps knives sharp without removing metal. Simply change the angle of the knife to sharpen, realign and polish. Professionals use chef's knives to readjust and maintain a sharp edge, but this skill takes a lot of practice. Get the same results faster with these triple-action knife sharpeners. The smooth edge presses the blade to the correct angle. Works equally well on straight and serrated blades to stay sharp. Safe to use the highest quality knives. Realign edges before flipping and darkening. Polish micro-bevels on the finest tableware without worrying about damaging the blade. These two steps will keep the knife sharp without removing any metal. Perfect for Japanese or Damascus knives, or any knife. Instructions are printed on the bottom.