Hello,
You can see the FW version of your RUT240 at the Top right corner of the WEB UI.
Or WEB UI-> System-> Firmware
If you want to know the FW version via CLI you can try:
root@Teltonika-RUT955:~# cd ..
root@Teltonika-RUT955:/# cd etc/config/
root@Teltonika-RUT955:/etc/config# cat system
Best Regards,
Akash R