Conduit Locknut, Trade Size 3-1/2 Inch, Diameter 4.75 Inch, Thickness 0.39 Inch, Material Aluminum, Installation 8 TPI Threaded, Approval UL 514B, CSA C22.2, Applicable Standard W-F-408E, NEMA FB-1, Application Used Where there is a Concern with Fasteners Becoming Loose, Used On IMC/Rigid Conduit