DIN 603   

*All measurements in millimeters (mm)*

  d d1 max k max f max b to 125 b to 200 b over 200
M5 13.55 3.3 4.1 16 - -
M6 16.55 3.88 4.6 18 24 -
M8 20.65 4.88 5.6 22 28 -
M10 24.65 5.38 6.6 26 32 45
M12 30.65 6.95 8.75 30 36 49
M16 38.8 8.95 12.9 38 44 57
M20 46.8 11.05 15.9 - - 46

All information is strictly informative