Guhring - M4x0.50 Metric Fine 3 Flute 6H Modified Bottoming Spiral Flute Tap - Cobalt, TiN Finish, 63mm OAL, Right Hand Flute, Right Hand Thread, D3/D4, Series 2897

Modified bottoming chamfers are similar to bottoming chamfers, but they are longer and have more teeth. They are used for threading blind holes and have 2 to 2-1/2 threads.

Cobalt is harder than high speed steel and provides better wear resistance. It is commonly used on high tensile alloys.

Titanium Nitride (TiN) is a multi-purpose coating which increases chip flow in softer materials. The heat and hardness resistance allows the tool to run at higher speeds than uncoated tools.

Slow Spiral Flutes with 8-20 degree angles are used for tough materials like high nickel alloys, titanium and some series of stainless steels.