Even a good knife will lose some of its sharpness with time. A sharpening steel, or honing steel, are rods that have a roughly ground surface that enables repairing or straightening a fine edge knife. It is important to ensure the hardness of the material in the sharpening steel exceeds that of the knife, or you may damage both pieces. Available in a variety of lengths, steels are slightly magnetic so they'll pick up particles of metal removed from the knife during honing. Over time, the honing steel surface becomes smooth and needs to be replaced. A neglected knife that is too dull cannot be repaired through honing and must be re-sharpened. Watch Henckels how-to video and learn to properly hone a knife.