The Terex interchangeable spiral bullet head is manufactured with a 1" lower flighting and a 1/2" upper flighting. This auger drills hard materials that conventional augers cannot.
Standard components are as follows:
Teeth- C10 RC1LR-SN (65349085)
Pilot: C10-6T-SP (65357524)
Application:
The Terex interchangeable spiral bullet head is designed specifically to improve the drilling performance of digger derrick augers in extreme conditions. This auger has a unique cutting pattern that allows each tooth to cut a small track to increase cutting efficiency and tooth life. The cut pattern and tooth attack angle combine to allow the bullet teeth to act as "fingers" that penetrate through and lift up fractured or broken material. In many cases a digger derrick equipped with a BTA spiral auger can drill in conditions previously requiring a pressure digger. | 
