Victorinox 2-Stage Knife Sharpener with Ceramic RollsHand held ceramic sharpener for all types of kitchen knives with two stage coarseness adjustment. Professionals sharpen the knives with a sharpener after each use. However, in a domestic environment, one use of the knife is short enough that it does not need to be sharpened as often. The knives you use most often need to be sharpened about once a month, for example with this handy long life sharpener.