This tool is used for isolation milling on a PCB. It is similar to isolation milling V-tool, but has 15º angle, comparing to 90º on V-tool. This results in a much more consistent width of cut, as imperfections of laminate level have minimal impact on the width.
The tool is supplied with a stopper ring, allowing hassle-free tool change operations
The shank measures 3.175 (1/8") in diameter.