Spiral Flute 45 deg DIN 5156.
Cobalt steel tools are similar to high-speed steel, but with more cobalt for improved performance when cutting harder metals such as stainless steel or nickel alloys.
Black oxide treatment adds lubricity and creates small pockets on the surface of the tool that act to hold coolant near the cutting edge.
When run in a counterclockwise direction (right-hand cut) spiral fluted tools evacuate chips up and out of the cut to reduce clogging.
Round with square end shank.