COMMON STANDARD CODES
| CODE | ASSOCIATION |
| API | AMERICAN PETROLEUM INSTITUTE |
| BA | BRITISH ASSOCIATION |
| BSF | BRITISH STANDARD FINE |
| BSP | BRITISH STANDARD PIPE |
| BSPT | BRITISH STANDARD PIPE TAPER |
| BSW | BRITISH STANDARD WHITWORTH |
| G | BRITISH STANDARD PIPE PARALLEL |
| ISO | INTERNATIONAL STD. ORGANIZATION |
| NC | AMERICAN NATIONAL COARSE |
| NF | AMERICAN NATIONAL FINE |
| NEF | AMERICAN NATIONAL EXTRA FINE |
| NPS | AMERICAN NATIONAL PIPE |
| NPSF | AMERICAN NATIONAL PIPE STD. FUEL |
| NPT | AMERICAN NATIONAL PIPE TAPER |
| NPTF | AMERICAN NATIONAL PIPE TAPER FUEL |
| PG | METRIC ELECTRICAL THREADS |
| R | BRITISH STANDARD PIPE TAPER |
| UN | UNIFIED NATIONAL |
| UNC | UNIFIED NATIONAL COARSE |
| UNF | UNIFIED NATIONAL FINE |
| UNS | UNIFIED NATIONAL SPECIAL |
| UNEF | UNIFIED NATIONAL EXTRA FINE |
| W | BRITISH STANDARD WHITWORTH |