| Larger size general purpose drills with 1/2 in reduced shank |
| Round shank or shank with three flats for a more positive grip in the drill chuck, flats reduce drill slippage under high load |
| Standard overall length and flute length for increased rigidity, less deflection and better hole accuracy |
| Standardized lengths result in minimal adjustment during tool changes in screw machines and machining centers |
| Black oxide surface finish increases wear resistance and adds lubricity, improving chip flow |
| For portable drilling due to increased rigidity |
