Question about Gigaset Comfort 500 A Duo (CH-Version)

In most cases, it is the power supply connector.

Here is the answer from Gigaset:
...our devices are all designed for the respective country for which they are sold. In addition to the connection cables, this also applies to the programming of the network signals, for example, which often differ from country to country. We therefore cannot recommend using them abroad, as we cannot guarantee perfect functionality in this case. In our online shop for German, we naturally sell German device variants, while in our online shop for Switzerland we sell devices designed for Switzerland. You are therefore welcome to take a look at our Swiss online shop.
https://www.gigaset.com/ch_de...
I hope it helps

Mains plug ... I would say! Incidentally, the device is extremely stable and can easily withstand a fall from the 3rd floor