| Screw Thread | M20 | ||
| Thread Size | M20 | ||
| D | 20 | ||
| P | Series 1 | Coarse Thread | 2.5 |
| P | Series 2 | Fine Thread | 2 |
| P | Series 1 | Fine Thread | 1.5 |
| Da | Min | 20 | |
| Da | Max | 21.6 | |
| Dk | Max | 28 | |
| Dw | Min | 28.3 | |
| E | Min | Grade A | 33.53 |
| E | Min | Grade B | 32.95 |
| X | Max | Series 1 | None |
| X | Max | Series 2 | None |
| G | Max | Series 1 | 9.3 |
| G | Max | Series 2 | 5.6 |
| H | Max | 34 | |
| H | Min | Grade A | 33.38 |
| H | Min | Grade B | 33 |
| M | Max | 16 | |
| M | Min | 14.9 | |
| Mw | Min | 11.92 | |
| SR | 14 | ||
| S | Max | 30 | |
| S | Min | Grade A | 29.67 |
| S | Min | Grade B | 29.16 |
| T | Min | 25.58 | |
| T | Max | 26.42 | |
| W | Min | 5 | |
| W | 104 | ||