30-Amp Non-Metallic Power Inlet Box

This is a question that is best answered by your local building authorities. Codes will vary from state to state and municipality to municipality.

No. There is a spring loaded cover over the inlet that keeps it covered when not in use but there is no provision for locking it.

It's a PVC-like material. Any "fusion" type of spray paint intended for lawn furniture and such would work.

Yes - It is rated to be water tight. Make sure you use the appropriate conduit attachment with a rubber gasket. You can also seal the attachment with an additional bead of silicon sealer. I also ran a bead of silicon across the top of the panel where it met the wall to keep water from entering from the backside (my wall has no overhang). I also sealed the attachment screw holes inside the box with silicon.

Yes, it is a "twist" lock style connector. You can position the connector by rotating it so that the "keyed" blade is in a more desirable position when you remove the connector for wiring.

Yes, this inlet box is labelled cULus for use in the US and Canada.

Yes, it came with a male 4 prong, 30 amp connector.

No the PBN30 is designed for generators around 5500 running watts, you would need to step up to the PBN50 for your size generator.

This is a 120/240 volt device so there are four wires: two hots, a neutral, and a ground. The wires come in to the inlet box through one of the knockouts in the side or back of the box and then are easily connected to the terminals on the power inlet. The bottom of the inlet box slides out for easy access to all four terminals.