Generally, the BrosTrend WiFi range extender’s SSID has a suffix _EXT/5GEXT added to the network name of your main router. But, you can always customize it. These extensions are to differentiate between a 2.4GHz and 5GHz network of the extender. Also, the WiFi password of the extender is as same as the main/root router. https://trendtracker.us/how-to-change-brostrend-extender-settings-and-re-extend-wifi/