Steel City Plastic Locknut

Three trade sizes: 1/2 inch (LN-501), 3/4 inch (LN-502) and 1 inch (LN-503). Pick the locknut to match the trade size of the conduit or connector thread it is going onto, not the knockout diameter.

Steel locknuts bite into the enclosure and are what you use where the connection has to carry fault current and serve as the equipment grounding path. A plastic locknut like the Steel City LN-501 series is non-conductive, so use it as a sealing or retaining nut, or on the inside of a box where a separate grounding means is already established. If the raceway is your ground path, use a steel locknut instead.

Yes. These are trade-size locknuts in 1/2, 3/4 and 1 inch, cut to the standard NPT-style conduit thread used on rigid conduit, IMC and EMT connectors, so a 1/2 inch locknut runs onto any 1/2 inch trade size male thread entering a box.

The locknut only retains the fitting in the knockout. If the enclosure has to keep water or dust out, you need a separate sealing washer or gasket on the outside of the box along with the locknut. Order those as a separate line item; nothing is packed with these locknuts.

Yes, the 1/2 inch plastic locknut is a bulk item, which is how MRO and contractor buyers usually take them for panel and box work rather than in small packs.