Precautions for use:
1, Please don't stack the files with other tools.
2, Please always remove debris from the surface of the files
3, Please don't use too much force to avoid breaking when using the needle files.
4, Do not use a new file to rub the hard metal with a hardness greater than HRC55.
5, Please use one side of the file first, then use the other side when the surface is blunt.
6, For the forgings that with hard or sticky sand, they must be ground on the grinder before they can be rubbed by a file.