BS EN ISO 4762: 2004 Metric hexagon socket head screws

ISO 10683, Fasteners – Non-electrolytically applied zinc flake coatings.
ISO 23429, Gauging of hexagon sockets.
See Fig. 1 and BS EN ISO 4762: 2004
Dimensions
Note: Symbols and designations of dimensions are defined in ISO 225.

Figure 1

Dimension in mm

aP = pitch of the thread.
b For lengths between the bold stepped lines in the unshaded area.
c For plain heads.
d For knurled heads.
eemin = 1,14 smin.
fCombined gauging of socket dimensions e and s, see ISO 23429.
gThe range of commercial lengths is between the bold stepped lines. Lengths in the shaded area are threaded to the head within 3P. Lengths below the shaded area have
values of lg and ls in accordance with the following formulae:
lg,max = lnom = b; ls,min = lg,max = 5P.
h The size in brackets should be avoided if possible.