Knives that no longer cut sharp over time? Very annoying. With a sharpening steel, you can straighten out burrs that occur over time. By sharpening the knife, you will continue to enjoy cutting your ingredients. The knives from the Wusthof series should be sharpened at an angle of 14°. An exception is made for the santoku knife, which requires an angle of 11°. The rod has a length of 23 cm and a hardness of 65 HRC.