This is a tool that we use when we need to remove a lot of material. It designed for rough milling in Aluminium and other soft long chipping materials. The surface finish is very rough. So you always need to use another mill (endmill) for finishing. The advantage of a Roughing Mill is that its a lot less sensitive for breaking due to chips getting stuck between the flutes.
These are mini endmills which work very nice with the kress and other hobby motors. The pricing is quite nice. It has some features which makes it nice for the hobbyist. It no problem to drill with this endmill for example.Another nice feature is the clamped diameter of all these mills is 6mm. So you dont need special clamps.