They exist ....

... The mounting devices. That's just sometimes like that. But with such a nice ran the Exchange, or the resending of totally uncomplicated.
Now the device. The problem was with the 1st unit that it never - not lit a red light - even when quite sure empty batteries.
The permanent color was green.
With the replacement unit everything works as it should be and as expected. A small practical and more than reasonably priced device, if one makes sure the batteries fit and insert pairs.
I'm very satisfied because I constantly use my mobile phone here.