Question about SumUp 3G + WiFi card reader

My question is actually about which band or bands can be used by this device. As we know, Swisscom has sometimes converted the former 3G standard band (2100Mhz) for newer technologies.
We had to make this experience with other devices that were supposedly upgraded to 3G and then suddenly only ran on 2G again. Until we realised that the devices only supported the 2100 band. Thus worthless for 3G.

Hello, yes this device goes via 3G. However, I must say that the connection ( maybe only in my shop) is very very slow.