Under the Device details section of the connected devices on your network, there is a section that provides more insight into how that specific device is currently connected to your network and whether or not it is using the 2.4 or 5 GHz frequency.
Here is a breakdown of the different connection types:
When your devices are connected to your network wirelessly, they’ll use the 2.4 or 5 GHz frequency. The big difference between these two frequencies is range vs. speed. With the 2.4 frequency, the waves are much wider and are able to provide you with greater coverage at greater distances. However, because of the wavelengths, data may travel slower. Whereas with the 5 GHz frequency, the waves are narrower and aren’t capable of traveling as far. You will be able to achieve the highest download and upload speeds when on 5 GHz.
When on a wireless network, either the 2.4 or 5 GHz frequency, the strength of your device to the eero network is represented in five status bars.