There is no transfer switch. All it does is provide a signal to a smart meter telling it that if the generator is plugged in, keeping open the contacts in the meter that the PoCo uses to disconnect power. So as long as the generator is plugged in there is no connection to the grid, meaning you cannot use this for on-line automatic backup. It only works so that AFTER the power fails, you plug in the generator. For a lot of people, that's fine.
One thing these smart meters is doing, that I just found out about, is that the contactor in them drops out on a power failure, but the PoCo decides when to turn it back on again. That way, they control surges when power is restored. If you have one of these sockets installed, they just do NOT re-close your meter contactor until AFTER you unplug the generator. By the way if you DON'T already have a smart meter, you GET one when you ask them to install this whether you want it or not.
So a slight annoyance to that is that if you don't pay attention to what's going on at your neighbor's house, or HE has one of these too, how do you know when to unplug the generator? Street lights will tell you if it's dark, but what about in the day?