Heavy jam nuts tend to be thinner than standard heavy hex nuts; however, possess the same dimension, especially across corners and flats. There are two common applications of heavy hex jam nuts. It is possible to thread a heavy 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. As hot-dip galvanizing generally adds 2.2 - 5 mils thickness to a fastener’s threaded portion, our galvanized heavy hex jam nuts get tapped oversize so as to balance the bolts’ corrosion resistant coating.