It is used to restore the sharpness of knives and can also be used for scissors.
The device appears to be a small, handheld electric sharpener with stainless steel accents and a power button.
Sharpening typically involves guiding the blade through the sharpener several times at the correct angle.
Regular sharpening helps in safer and more effective cooking by ensuring clean cuts.
The image context indicates instructions in Chinese for how to use the device.