[Fireman286]

Is there not a nut that should be on the back of the outlet, or you do you just twist it to lock it in to place.

 

[Marley]

Depends on the style. Some are threaded with a rubber washer and a nut. Some spring tabs that pop out to hold it in place.
(and some have surface mount bracket that use screws to mount it).

 

[Fireman286]

Thanks. I used it for my phone charger the other day and found mine had none of the above.