These screw-mount nuts have three mounting holes to accept screws and rivets. Insert the barrel through a hole or fasten the base with the barrel facing upward for use with thin materials. Since the base is flanged, it helps spread out the load. A larger base means more room for weight to spread. The longer the barrel, the more thread engagement with your screw.
Style B—Style B nuts can also be welded for a stronger, permanent hold. The three projections on their base concentrate your weld and create room for heat to dissipate, protecting threads from deforming.