The specifications of the shutter wheel are diverse, including but not limited to the following: Size: The size of the shutter wheel is wide, for example, the grinding disc size is 1050256, the shutter wheel size is 60256, 7025 (Huixiong, Duolihao and other brands), the shutter wheel (Dingkun, Jinxiang, etc.) has more sizes, such as 120100, 1001