The hex jam nuts appear thinner compared to a standard hex nut; however, across the corners and flats, they possess the same dimension. There are two common applications of Hex jam nuts. It is possible to thread a hex jam nut onto a bolt & run tight against a standard nut. This phenomenon locks the nut in place as well as prevents it from pulling back. These nuts are also used for leveling purposes.

Stock

Diameters: 1/2″ – 2″
Origin: Import
Finish: Plain and hot-dip galvanized

Dimensions

Click table to show drawingHex Jam Nut
Nominal Size F C H Part Numbers
Width Across Flats Width Across Corners Thickness
Basic Max Min Max Min Basic Max Min Plain Galvanized
1⁄2 3⁄4 0.750 0.736 0.866 0.840 5⁄16 0.323 0.302 11827 11828
5⁄8 15⁄16 0.938 0.922 1.083 1.051 3⁄8 0.387 0.363 11829 11830
3⁄4 11⁄8 1.125 1.088 1.299 1.240 27⁄64 0.446 0.398 11831 11832
7⁄8 15⁄16 1.312 1.269 1.516 1.447 31⁄64 0.510 0.458 11833 18834
1 11⁄2 1.500 1.450 1.732 1.653 35⁄64 0.575 0.519 11835 11836
11⁄8 111⁄16 1.688 1.631 1.949 1.859 39⁄64 0.639 0.579 11837 11838
11⁄4 17⁄8 1.875 1.812 2.165 2.066 23⁄32 0.751 0.687 11839 11840
13⁄8 21⁄16 2.062 1.994 2.382 2.273 25⁄32 0.815 0.747 19678 19679
11⁄2 21⁄4 2.250 2.175 2.598 2.480 27⁄32 0.880 0.808 11841 11842

Dimensions per ASME B18.2.2 1987 (1999)