Carbon Steel: 2H,2HM,7
m=height of the nut
d=the nominal diameter of the thread
E=The length of the diagonal
S=The length of the flat
Note: Chemical and mechanical properties of the heavy hexagonal nut shall conform to ASTM A 563 grades of ASTM A194/ A194M, Grade 2H.
The A194 nut's grade shall have a proof load capacity equal to or greater than the ultimate tensile strength of the bolt it will be used with.