Drop center face | For high penetration ratesin soft to medium-hard and fissured rock formations. Low to medium airpressures. Maximum hole deviation control. |
 Concave face
| The all-round applicationbit face specifically for medium hard and homogeneous rock formations. Goodhole deviation control and good flushing capacity. |
Convex face | For high penetration ratesin soft to medium-hard with low to medium air pressures. It is the mostresistance to steel wash, and may reduce the load and wear on the gaugebuttons, but poor hole deviation control. |
 Flat face
| This kind of face shape issuitable for hard to very hard and abrasive rock formations in applicationswith high air pressures. Good penetration rates an resistance to steel wash. |
Double gauge face | This kind of face shape issuitable for fast penetration rates in medium to hard rock formations. Designedfor high air pressures and good resistance to steel wash step gauge bit. |
