Finished Hex Nuts - N.F. / Fine Thread
Finished Hex Nuts              Finished Hex Nuts
Finished Hex Nuts
Nominal or 
Basic Major 
Diameter 
of Thread
F G H
Width Across Flats
(Wrench Size)
Width Across Corners Thickness of 
Hex Nuts
Basic Max Min Max Min Basic Max Min
1/4 0.2500 7/16 0.438 0.428 0.505 0.488 7/32 0.226 0.212
5/16 0.3125 1/2 0.500 0.489 0.577 0.557 17/64 0.273 0.258
3/8 0.3750 9/16 0.562 0.551 0.650 0.628 21/64 0.337 0.320
7/16 0.4375 11/16 0.688 0.675 0.794 0.768 3/8 0.385 0.365
1/2 0.5000 3/4 0.750 0.736 0.866 0.840 7/16 0.448 0.427
9/16 0.5625 7/8 0.875 0.861 1.010 0.982 31/64 0.496 0.473
5/8 0.6250 15/16 0.938 0.922 1.083 1.051 35/64 0.559 0.535
3/4 0.7500 1-1/8 1.125 1.088 1.299 1.240 41/64 0.665 0.617
7/8 0.8750 1-5/16 1.312 1.269 1.516 1.447 3/4 0.776 0.724
1" 1.0000 1-1/2 1.500 1.450 1.732 1.653 55/64 0.887 0.831
1-1/8 1.1250 1-11/16 1.688 1.631 1.949 1.859 31/32 0.999 0.939
1-1/4 1.2500 1-7/8 1.875 1.812 2.165 2.066 1-1/6 1.094 1.030
1-3/8 1.3750 2-1/16 2.062 1.994 2.382 2.273 1-11/64 1.206 1.138
1-1/2 1.5000 2-1/4 2.250 2.175 2.598 2.480 1-9/32 1.317 1.245
1-5/8 1.6250 2-7/16 2.438 2.356 2.815 2.686 1-25/64 1.429 1.353
1-3/4 1.7500 2-5/8 2.625 2.538 3.031 2.893 1-1/2 1.540 1.460
2" 2.0000 3" 3.000 2.900 3.464 3.306 1-23/32 1.763 1.675
2-1/4 2.2500 3-3/8 3.375 3.263 3.897 3.719 1-15/16 1.986 1.890
2-1/2 2.5000 3-3/4 3.750 3.625 4.330 4.133 2-5/32 2.209 2.105
2-3/4 2.7500 4-1/8 4.125 3.988 4.763 4.546 2-3/8 2.431 2.319
3" 3.0000 4-1/2 4.500 4.350 5.196 4.959 2-19/32 2.654 2.534