Guhring - M4x0.70 Metric Coarse H6 Thread Limit Modified Bottoming Thread Forming Tap - Cobalt, TiCN Finish, 2.13" OAL, 0.295" Thread Length, Right Hand Thread, Series 3942

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

Titanium carbonitride (TiCN) is harder and more wear resistant than TiN. It is used on stainless steels, cast iron and aluminum alloys.

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