BSB British Standard Brass Thread. Used brass tubing. BSB has a 26 TPI pitch through the whole range.
The flank angle is 55°.
| Nominal Dia. | TPI | Pitch mm | Tap/Drill mm |
|---|
| G 1/16” | 6.561 | 28 | 0.907 |
| G 1/8” | 8.565 | 28 | 0.907 |
| G 1/4” | 11.445 | 19 | 1.337 |
| G 3/8” | 14.95 | 19 | 1.337 |
| G 1/2” | 18.633 | 14 | 1.814 |
| G 3/4” | 24.12 | 14 | 1.814 |
| G 1” | 30.292 | 11 | 2.309 |
| G 1 1/4” | 38.953 | 11 | 2.309 |
| G 1 1/2” | 44.846 | 11 | 2.309 |
| G 2” | 56.657 | 11 | 2.309 |
| G 2 1/2” | 72.227 | 11 | 2.309 |
| G 3” | 84.927 | 11 | 2.309 |
| G 4” | 110.073 | 11 | 2.309 |
| G 5” | 135.473 | 11 | 2.309 |
| G 6” | 160.873 | 11 | 2.309 |
| Nominal Dia. | Diameter inch | Diameter mm | — |
|---|
| G 1/16” | 0.063 | 7.722 | — |
| G 1/8” | 0.125 | 9.728 | — |
| G 1/4” | 0.25 | 13.157 | — |
| G 3/8” | 0.375 | 16.662 | — |
| G 1/2” | 0.5 | 20.955 | — |
| G 3/4” | 0.75 | 26.441 | — |
| G 1” | 1 | 33.249 | — |
| G 1 1/4” | 1.25 | 41.91 | — |
| G 1 1/2” | 1.5 | 47.803 | — |
| G 2” | 2 | 59.614 | — |
| G 2 1/2” | 2.5 | 75.184 | — |
| G 3” | 3 | 87.884 | — |
| G 4” | 4 | 113.03 | — |
| G 5” | 5 | 138.43 | — |
| G 6” | 6 | 163.83 | — |