
*All measurements in millimeters (mm)*
d | s | e | m |
M3 | 5.5 | 7 | 1.8 |
M4 | 7 | 8.9 | 2.2 |
M5 | 8 | 10.2 | 2.7 |
M6 | 10 | 12.7 | 3.2 |
M8 | 13 | 16.5 | 4 |
M10 | 17 | 21.5 | 5 |

*All measurements in millimeters (mm)*
d | b | t min | s | k max | d1 |
M2 | 16 | 1 | 1.5 | 2 | 3.8 |
M3 | 18 | 1.3 | 2.5 | 3 | 5.5 |
M4 | 20 | 2 | 3 | 4 | 7 |
M5 | 22 | 2.5 | 4 | 5 | 8.5 |
M6 | 24 | 3 | 5 | 6 | 10 |
M8 | 28 | 4 | 6 | 8 | 13 |
M10 | 32 | 5 | 8 | 10 | 16 |
M12 | 36 | 6 | 10 | 12 | 18 |
M14 | 40 | 7 | 12 | 14 | 21 |
M16 | 44 | 8 | 14 | 16 | 24 |
M18 | 48 | 9 | 14 | 18 | 27 |
M20 | 52 | 10 | 17 | 20 | 30 |
M24 | 60 | 12 | 19 | 24 | 36 |
M27 | 66 | 13.5 | 19 | 27 | 40 |
M30 | 75 | 15.5 | 22 | 30 | 45 |
M36 | 84 | 19 | 27 | 36 | 54 |

*All measurements in millimeters (mm)*
d | d1 max | t min | e | s |
M2 | 1 | 0.8 | 1.003 | 0.9 |
M2.5 | 1.5 | 1.2 | 1.427 | 1.3 |
M3 | 2 | 1.2 | 1.73 | 1.5 |
M4 | 2.5 | 1.5 | 2.3 | 2 |
M5 | 3.5 | 2 | 2.87 | 2.5 |
M6 | 4 | 2 | 3.44 | 3 |
M8 | 5.5 | 3 | 4.58 | 4 |
M10 | 7 | 4 | 5.72 | 5 |
M12 | 8.5 | 4.8 | 6.86 | 6 |
M14 | 10 | 5.6 | 6.86 | 6 |
M16 | 12 | 6.4 | 9.15 | 8 |
M20 | 15 | 8 | 11.43 | 10 |
M24 | 18 | 10 | 13.72 | 12 |

*All measurements in millimeters (mm)*
d | d1 max | t min | e | s |
M3 | – | 1.2 | 1.73 | 1.5 |
M4 | – | 1.5 | 2.3 | 2 |
M5 | – | 2 | 2.87 | 2.5 |
M6 | 1.5 | 2 | 3.44 | 3 |
M8 | 2 | 3 | 4.58 | 4 |
M10 | 2.5 | 4 | 5.72 | 5 |
M12 | 3 | 4.5 | 6.86 | 6 |
M16 | 4 | 6.4 | 9.15 | 8 |
M20 | 5 | 8 | 11.43 | 10 |

*All measurements in millimeters (mm)*
d | d1 max | t min* | e | s |
M2 | 1 | 0.8 | 1.003 | 0.9 |
M2.5 | 1.2 | 1.2 | 1.427 | 1.3 |
M3 | 1.4 | 1.2 | 1.73 | 1.5 |
M4 | 2 | 1.5 | 2.3 | 2 |
M5 | 2.5 | 2 | 2.87 | 2.5 |
M6 | 3 | 2 | 3.44 | 3 |
M8 | 5 | 3 | 4.58 | 4 |
M10 | 6 | 6 | 5.72 | 5 |
M12 | 8 | 8 | 6.86 | 6 |
M14 | 9 | 9 | 6.86 | 6 |
M16 | 10 | 10 | 9.15 | 8 |
M20 | 14 | 12 | 11.43 | 10 |
M24 | 16 | 15 | 13.72 | 12 |

*All measurements in millimeters (mm)*
d | k | e | s |
M3 | 2 | 6.01 | 5.5 |
M4 | 2.8 | 7.66 | 7 |
M5 | 3.5 | 8.79 | 8 |
M6 | 4 | 11.05 | 10 |
M8 | 5.3 | 14.38 | 13 |
M10 | 6.4 | 18.9 | 17 |
M12 | 7.5 | 21.1 | 19 |
M14 | 8.8 | 24.49 | 22 |
M16 | 10 | 26.75 | 24 |
M18 | 11.5 | 30.14 | 27 |
M20 | 12.5 | 33.53 | 30 |
M22 | 14 | 35.72 | 32 |
M24 | 15 | 39.98 | 36 |
M27 | 17 | 45.2 | 41 |
M30 | 18.7 | 50.85 | 46 |
M33 | 21 | 55.37 | 50 |
M36 | 22.5 | 60.79 | 55 |
M42 | 26 | 71.3 | 65 |
M48 | 30 | 82.6 | 75 |

*All measurements in millimeters (mm)*
d | s | e | m |
M1.6 | 3.2 | 3.48 | 1.3 |
M2 | 4 | 4.32 | 1.6 |
M2.5 | 5 | 5.45 | 2 |
M2.6 | 5 | 5.51 | 2 |
M3 | 5.5 | 6.01 | 2.4 |
M3.5 | 6 | 6.01 | 2.8 |
M4 | 7 | 7.66 | 3.2 |
M5 | 8 | 8.76 | 4 |
M6 | 10 | 11.05 | 5 |
M7 | 11 | 12.12 | 5.5 |
M8 | 13 | 14.38 | 6.5 |
M10 | 17 | 18.9 | 8 |
M12 | 19 | 21.1 | 10 |
M14 | 22 | 24.49 | 11 |
M16 | 24 | 26.75 | 13 |
M18 | 27 | 29.56 | 15 |
M20 | 30 | 32.95 | 16 |
M22 | 32 | 35.03 | 18 |
M24 | 36 | 39.55 | 19 |
M27 | 41 | 45.2 | 22 |
M30 | 46 | 50.85 | 24 |
M33 | 50 | 55.37 | 26 |
M36 | 55 | 60.79 | 29 |
M39 | 60 | 66.44 | 31 |
M42 | 65 | 71.3 | 34 |
M45 | 70 | 76.95 | 36 |
M48 | 75 | 82.6 | 38 |
M52 | 80 | 88.25 | 42 |
M56 | 85 | 95.07 | 45 |
M60 | 90 | 100.72 | 48 |

*All measurements in millimeters (mm)*
d | s | e | m min | m1 min | h |
M3 | 5.5 | 6.01 | 2.4 | 1.65 | 4 |
M4 | 7 | 7.66 | 2.9 | 2.2 | 5 |
M5 | 8 | 8.79 | 3.2 | 2.75 | 5 |
M6 | 10 | 11.05 | 4 | 3.3 | 6 |
M8 | 13 | 14.38 | 5.5 | 4.4 | 8 |
M10 | 17 | 18.9 | 6.5 | 5.5 | 10 |
M12 | 19 | 21.1 | 8 | 6.6 | 12 |
M14 | 22 | 24.49 | 9.5 | 7.7 | 14 |
M16 | 24 | 26.75 | 10.5 | 8.8 | 16 |
M18 | 27 | 29.56 | 13 | 9.9 | 18.5 |
M20 | 30 | 32.95 | 14 | 11 | 20 |
M22 | 32 | 35.03 | 15 | 12.2 | 22 |
M24 | 36 | 39.55 | 15 | 13.2 | 24 |

*All measurements in millimeters (mm)*
d | s | e | m | d1 |
M6 | 10 | 11.05 | 6 | 14.2 |
M8 | 13 | 14.38 | 8 | 17.9 |
M10 | 15 | 16.64 | 10 | 21.8 |
M12 | 18 | 20.03 | 12 | 26 |
Form C, with drilling tip

*All measurements in millimeters (mm)*
d | k max | d1 max | r1 approx | Cross recess No. |
2.2 | 1.8 | 4.2 | 3.4 | H1 |
2.9 | 2.2 | 5.6 | 4.4 | H1 |
3.5 | 2.6 | 6.9 | 5.4 | H2 |
3.9 | 2.8 | 7.5 | 5.8 | H2 |
4.2 | 3.05 | 8.2 | 6.2 | H2 |
4.8 | 3.55 | 9.5 | 7.2 | H2 |
5.5 | 3.95 | 10.8 | 8.2 | H3 |
6.3 | 4.55 | 12.5 | 9.5 | H3 |
8 | 5.25 | 15.8 |
Form C, with drilling tip

*All measurements in millimeters (mm)*
d | d1 max | k approx | Cross Recess No. |
2.2 | 4.3 | 1.3 | H1 |
2.9 | 5.5 | 1.7 | H1 |
3.5 | 6.8 | 2.1 | H2 |
3.9 | 7.5 | 2.3 | H2 |
4.2 | 8.1 | 2.5 | H2 |
4.8 | 9.5 | 3 | H2 |
5.5 | 10.8 | 3.4 | H3 |
6.3 | 12.4 | 3.8 | 3 |
8 | 15.8 | 4.65 | ?? |

*All measurements in millimeters (mm)*
d | b | t | e | s | k max | d1 |
M3 | 12 | 1.2 | 2.3 | 2 | 1.7 | 6 |
M4 | 14 | 1.8 | 2.87 | 2.5 | 2.3 | 8 |
M5 | 16 | 2.3 | 3.44 | 3 | 2.8 | 10 |
M6 | 18 | 2.5 | 4.58 | 4 | 3.3 | 12 |
M8 | 22 | 3.5 | 5.72 | 5 | 4.4 | 16 |
M10 | 26 | 4.4 | 6.86 | 6 | 5.5 | 20 |
M12 | 30 | 4.6 | 9.15 | 8 | 6.5 | 24 |
M16 | 38 | 5.3 | 11.43 | 10 | 7.5 | 30 |
M20 | 46 | 5.9 | 13.72 | 12 | 8.5 | 36 |
M24 | 54 | 10.3 | 16 | 14 | 14 | 39 |
ISO 7380 Button Head Sockets
Nominal Screw Diameter and Thread Pitch | A | H | S | J | T | ||
Head Diameter | Head Height | Head Side Height | Hexagon Socket Size | Key Engagement | |||
Min. | Max. | Min. | Max. | Ref. | Nom. | Min. | |
M3 x 0.5 | 5.40 | 5.70 | 1.43 | 1.65 | 0.38 | 2.0 | 1.04 |
M4 x 0.7 | 7.24 | 7.60 | 1.95 | 2.20 | 0.38 | 2.5 | 1.30 |
M5 x 0.8 | 9.14 | 9.50 | 2.50 | 2.75 | 0.50 | 3.0 | 1.56 |
M6 x 1 | 10.07 | 10.50 | 3.00 | 3.30 | 0.80 | 4.0 | 2.08 |
M8 x 1.25 | 13.57 | 14.00 | 4.05 | 4.40 | 0.80 | 5.0 | 2.60 |
M10 x 1.5 | 17.07 | 17.50 | 5.20 | 5.50 | 0.80 | 6.0 | 3.12 |
M12 x 1.75 | 20.48 | 21.00 | 6.24 | 660 | 0.80 | 8.0 | 4.16 |
M16 x 2 | 27.48 | 28.00 | 8.44 | 8.80 | 1.5 | 10.0 | 5.20 |
Nominal Screw Diameter and Thread Pitch | G | B | E | F | L | |
Wall Thickness | Under Head Fillet | Maximum Standard Length | ||||
Transition Diameter | Transition Length | Juncture Radius | ||||
Min. | Min. | Max. | Max. | Min. | Nom | |
M3 x 0.5 | 0.20 | 3.2 | 3.6 | 0.51 | 0.10 | 12 |
M4 x 0.7 | 0.30 | 4.4 | 4.7 | 0.60 | 0.20 | 20 |
M5 x 0.8 | 0.38 | 5.4 | 5.7 | 0.60 | 0.20 | 30 |
M6 x 1 | 0.74 | 6.5 | 6.8 | 0.68 | 0.25 | 30 |
M8 x 1.25 | 1.05 | 8.8 | 9.2 | 1.02 | 0.40 | 40 |
M10 x 1.5 | 1.45 | 10.8 | 11.2 | 1.02 | 0.40 | 40 |
M12 x 1.75 | 1.63 | 13.2 | 14.2 | 1.87 | 0.60 | 60 |
M16 x 2 | 2.25 | 17.2 | 18.2 | 1.87 | 0.60 | 60 |