In the US the 240v outlet is a physically different shape and size, and there's usually only a few in each home, where powerful appliances are expected to be fi

In the US the 240v outlet is a physically different shape and size, and there's usually only a few in each home, where powerful appliances are expected to be fitted. You could probably fit an adapter, but I imagine smart plugs in the US are built with the assumption they will never have to handle such a high load.