Hoi - there are various possibilities and options to operate the part in the FC with an appropriate antenna - I use it "as Is" with the plug-in antennas on it, as well as appropriate antennas for WiFi and GPS. If you want another one: Can you please write me how you want to use it in the FC (which FC approximately) or what your plan is? There are puk antennas, radome-like etc... (but maybe not here in the shop :) ).
The cables are HF (HighFrequency) with SMA. Cables that are too long have a negative influence on reception... LG

It's actually only enough for 5G, if it can also do GPS/WIFI would be ok too.
And what are the extension cables called? Are they also available in the Digitec shop?