API Steel Tooth/TCI Oil Well Rock Bit
Soft formation tooth bits:

The soft formations tooth bits are used to drill low compressive strength, soft formations. Long projection tooth lengths are used on high offset cones to provide the greatest penetrations rates possible. Wear resistance hard facing is used to control tooth wear. On the softest bit types this hard facing completely covers the bit teeth.

 

Medium hard formations tooth bits:

The medium hard formation tooth bits are used to drill high compressive strength, medium hard formations. Shoot projection teeth with reduced crest length are used in this series of bit designs. Durable hard facing is applied to reduce tooth wear.