Thomas & Betts Insulated Liquid-Tight Connector - Straight

Two trade sizes: 3 inch and 4 inch. The 3 inch is Thomas & Betts part 5339. Both are straight (non-angled) insulated liquid-tight connectors for large-diameter liquid-tight flexible metal conduit, so match the connector trade size to the conduit trade size, not to the conduit's outside diameter.

Yes. The 5339 is the 3 inch trade size, so it lands in a 3 inch conduit knockout or a 3 inch threaded hub. If your enclosure opening is 4 inch, order the 4 inch version instead rather than trying to bush down a large opening.

That is what it is built for. It is a liquid-tight connector, and the malleable iron body suits exterior and industrial wet-location runs on LFMC. It does not, on its own, cover the enclosure-side gasketing, so the knockout still has to be sealed for the location.

These insulated liquid-tight straight connectors are supplied with the gland assembly for the conduit side. On the enclosure side, plan on a locknut and, where a wet-location seal at the knockout is required, a sealing washer or gasket suited to the 3 or 4 inch hub, ordered separately. The fitting seals the conduit to the connector; it does not by itself make the box-wall penetration watertight.

At 3 and 4 inch you are pulling large conductors with real tension, and a bare metal throat edge is where insulation gets nicked on the pull. The insulated throat gives the conductors a smooth bearing surface entering the box, which is also what many inspectors look for on feeder-size pulls.