Dull knives are easily brought back to life with the WÜSTHOF diamond steel. A sharpening rod with a diamond coating should be used for dull or moderately sharp knives. The special shape of the diamond grit on the sharpening rod ensures exceptional sharpening of the knife blade. The result: a smooth, sharp edge. Use the same way as a regular honing steel - stroke the knife down the full length of the steel at 20 degree per side, 4-5 strokes per side and easy does. Note: Use only when knife is dull.