ISO 4017 Hexagon head screws – Basic dimensions
Selected sizes used for CE Marking under EN 15048
| Dimension (d) | M12 | M16 | M20 | M22 | M24 | M27 | M30 | M33 | M36 |
| Thread pitch (P) | 1.75 | 2 | 2.5 | 2.5 | 3 | 3 | 3.5 | 3.5 | 4 |
| k (nom) | 7.5 | 10 | 12.5 | 14 | 15 | 17 | 18.7 | 21 | 22.5 |
| k (Grade A) | 7.32-7.68 | 9.82-10.18 | 12.285-12.715 | 13.785-14.215 | 14.785-15.215 | – | – | – | – |
| k (Grade B) | 7.21-7.79 | 9.71-10.29 | 12.15-12.85 | 13.65-14.35 | 14.65-15.35 | 16.65-17.35 | 18.28-19.12 | 20.58-21.42 | 22.08-22.92 |
| s (nom) | 18 | 24 | 30 | 34 | 36 | 41 | 46 | 50 | 55 |
| s (min, Grade A) | 17.73 | 23.67 | 29.67 | 33.38 | 35.38 | – | – | – | – |
| s (min, Grade B) | 17.57 | 23.16 | 29.16 | 33.00 | 35.00 | 40.00 | 45.00 | 49.00 | 63.10 |
| e (min, Grade A) | 20.03 | 26.75 | 33.53 | 37.72 | 39.98 | – | – | – | – |
| e (min, Grade B) | 19.85 | 26.17 | 32.95 | 37.29 | 39.55 | 45.20 | 50.85 | 55.37 | 60.79 |
Dimensions in millimetres
| Size | Grade A | Grade B |
| M12 (l) | Up and including 120 | Including and above 125 |
| M16 (l) | Up and including 150 | Including and above 155 |
| M20 (l) | Up and including 150 | Including and above 155 |
| M22 (l) | Up and including 150 | Including and above 155 |
| M24 (l) | Up and including 150 | Including and above 155 |
| M27 (l) | – | All lengths |
| M30 (l) | – | All lengths |
| M33 (l) | – | All lengths |
| M36 (l) | – | All lengths |
