The KAI knife sharpener has a stylish and solid design and is easy to take with you. If you don't use it you can easily store the sharpener in a transparent plastic cover to make sure no dust or dirt can get caught in between the slots. If you use it you take out the sharpener and use the 'casing' as handle, for optimal stability while. Each of the three sharpening slots uses a different sharpening method. The first slot contains two small diamond sharpening stones with grain size 270. Relatively coarse and therefore perfect for the first sharpening phase to restore a blunt edge. sharpening.