Question about Varta LCD Multi Charger+

@digitec - could you please document the specific, correct power supply requirements for the product? You could then also make a product recommendation... I only see complaints here about what doesn't work, but nothing binding that says what is really needed. Some people here mention that a power supply unit is included. That actually used to be the case. But it seems that this product is being offered as the same one that was on sale years ago, back then with a power supply. I also have one of these. It tells me that I bought this product x years ago. But that was without USB.