This cutting wheel (shaft diameter 0.3 mm) is for mini routers that are easy to use for model making and customizing RC cars.
It can be used for cutting and processing plastic resins as well as for processing and cutting small amounts of light metal. The disc is 1mm thick, so it is a little thick, but it is a genuine disc grinding wheel made from fine sand molded into resin, and it has excellent durability and cutting speed. If the thickness of the whetstone is not a big concern for the work you are doing, this tool is extremely useful.