DIN 6921 Specifications:

 

All measurements in millimeters (mm)    
Diameter M6 M8 M10 M12 M16
b min 18 22 26 30 38
d2 max ~Min 14.2 to 12.70 18 to16.80 22.3 to 21.50 26.6-24.30 35-32.80
k max~Min 6.6 to 4.85 8.1 to 6.30 9.2 to 7.50 11.5 to 9.80 14.4 to 12.30
s max~Min 10 to 9.80 13 to 12.70 15 to 14.80 16 to 15.85 21 to 20.85
           
All information is strictly informative