HEX FINISHED JAM NUTS
DIMENSIONS
All Dimensions in inches
Nominal Size or 
Basic Major Dia. 
or Thread
Width Across Flats Width Across Corners Thickness
Basic Max. Min. Max. Min. Basic Max. Min.
1/4 0.2500 7/16 0.438 0.428 0.505 0.488 5/32 0.163 0.150
5/16 0.3125 1/2 0.500 0.489 0.577 0.557 3/16 0.195 0.180
3/8 0.3750 9/16 0.562 0.551 0.650 0.628 7/32 0.227 0.210
7/16 0.4375 11/16 0.688 0.675 0.794 0.768 1/4 0.260 0.240
1/2 0.5000 3/4 0.750 0.736 0.866 0.840 5/16 0.323 0.302
9/16 0.5625 7/8 0.875 0.861 1.010 0.982 5/16 0.324 0.301
5/8 0.6250 15/16 0.938 0.922 1.083 1.051 3/8 0.387 0.363
3/4 0.7500 1-1/8 1.125 1.088 1.299 1.240 27/64 0.446 0.398
7/8 0.8750 1-5/16 1.312 1.269 1.516 1.447 31/64 0.510 0.458
1 1.0000 1-1/2 1.500 1.450 1.732 1.653 35/64 0.575 0.519
1-1/8 1.1250 1-11/16 1.688 1.631 1.949 1.850 39/64 0.639 0.579
1-1/4 1.2500 1-7/8 1.875 1.812 2.165 2.066 23/32 0.751 0.687
1-3/8 1.3750 2-1/16 2.062 1.994 2.382 2.273 25/32 0.815 0.747
1-1/2 1.5000 2-1/4 2.250 2.175 2.598 2.480 27/32 0.880 0.808