Lewis pattern Augers have a cutting spur on one side, a main blade to clear waste on the other, a screw thread in the centre to pull the bit into the cut and a single broad channel to remove the waste. Engineered for use in hand held or stationary machines these augers perform beautifully boring deep holes in softwoods and European hardwoods.
All sizes have an overall length of 235mm and a cutting length of 160mm. See the table below for shaft diameter.
| auger size (mm) | shaft diameter (mm) |
| 6 | 5.5 |
| 9 | 8 |
| 10 | 9.8 |
| 12 | 11.8 |
| 16 | 13 |
| 18 | 13 |
| 20 | 13 |
| 22 | 13 |
| 24 | 13 |
| 26 | 13 |
