Do you have a faucet product with a specific inch/size measurement or the dimension in mm?
Then you can find the value in this table.


INTERNAL THREAD MM TO INCH
MM | INCH / SIZE |
approx. 9 | 1/8 |
approx. 11 | 1/4 |
approx. 15 | 3/8 |
approx. 19 | 1/2 |
approx. 20 | 5/8 |
approx. 24 | 3/4 |
approx. 30 | 1 |
approx. 39 | 1.1/4 |
approx. 45 | 1.1/2 |
approx. 57 | 2 |
approx. 72 | 2.1/2 |
approx. 85 | 3 |

EXTERNAL THREAD MM TO INCH
MM | INCH / SIZE |
approx. 10 | 1/8 |
approx. 13 | 1/4 |
approx. 17 | 3/8 |
approx. 21 | 1/2 |
approx. 23 | 5/8 |
approx. 26 | 3/4 |
approx. 33 | 1 |
approx. 42 | 1.1/4 |
approx. 48 | 1.1/2 |
approx. 60 | 2 |
approx. 75 | 2.1/2 |
approx. 89 | 3 |
The abbreviation US and BU stand for external thread
The abbreviation IS or BI stand for internal thread