;Round base nuts These nuts have a long threaded cylinder with a large circular base to make welding easy. They also sometimes have projections (known as weld nibs or bosses) to keep the nut from warping while welding with a high current. ;Slab base nuts These are very similar to the round base nuts, but with an
obround, or slab shaped, base. These are used in channels, tubes, or other tight quarters. ;Retainer weld nuts Retainer weld nuts, also known as bridge weld nuts, have a floating nut retained inside a retainer to compensate for inconsistencies. The retainer is welded to the work piece while the nut is allowed to float.
Four Projection Weld Nuts Four projections designed to fuse simultaneously so each projection flows and seats properly.
Single Tab Weld Nuts Single button projection weld nut for use on heavier gage materials. == Material ==