HEX NYLON INSERT LOCKNUTS
NU SERIES 
All Dimensions in Inches
Size Thickness Across
  Flats
Across 
Corners
Prevailing 
Torque 
in-lbs. Max.
Tensile Strength 
lbs. Min.
1/4-20 0.375 0.500 0.556 30.0 6.590
5/16-18 0.438 0.562 0.624 60.0 9.410
3/8-16 0.547 0.688 0.763 80.0 13.900
7/16-14 0.703 0.875 0.969 150.0 20.300
1/2-13 0.703 0.875 0.969 150.0 27.200
9/16-12 0.797 0.938 1.037 200.0 37.800
5/8-11 0.859 1.062 1.175 300.0 44.100
3/4-10 1.000 1.250 1.382 400.0 59.200
7/8-9 1.125 1.438 1.589 600.0 80.100
1-8 1.281 1.625 1.796 800.0 105.000
1-1/8-7 1.438 1.812 2.002 900.0 132.000
1-1/4-7 1.641 2.000 2.209 1.000.0 169.000
1-3/8-6 1.797 2.188 2.416 1.200.0 207.000
1-1/2-6 1.922 2.375 2.622 1.350.0 240.000
1-3/4-5 2.313 2.750 3.035 1.400.0 -
2-4-1/2 2.406 3.125 3.449 1.450.0 -