The composition of the stone affects the sharpness of the blade (a finer grain, usually, though not always, produces sharper blades), as does the composition of the blade (some metals take and keep an edge better than others). For example, Western kitchen knives are usually made of softer steel and take an edge angle of 20–22°, while East Asian kitchen knives are traditionally of harder steel and take an edge angle of 15–18°. The Western-style kitchen knives are generally in the range of 52–58 on the Rockwell scale, which denotes the relative hardness of a material.
It looks like it can be a Sci-Fi film prop. This is a 2 stage type of sharpening system. You'll get a non slip cushion with it which is at the bottom offering stability for the user. It's ergonomic handle provides a comfortable and easy grip. This cushion offers the stability needed when sharpening and polishing your pocket knife to it's absolute razor sharpness. The sharpener does the work as you hold down the grip and simply place your pocket knife to get sharpened by the motions of the ceramic and diamond sharpener wheels. Simply run your dull knives through the device and you'll get the results you've been looking for. This one will definitely help you when you learn how to sharpen a pocket knife on the Priority Chef.