Waveform QuadPro Antenna, works great tor improving 5G / LTE signals, we used it to improve T-Mobile Home Internet as we are far from the tower. Also works with AT&T and Verizon. Has 4 SMA connectors so make sure your device has or you can convert to use those. The G4AR and G4SE T-Mobile gateways are among those compatible.
We now have fiber rolled out so no longer need this but it was invaluable when we had it. Could do with a bit of a clean from being out in the elements this past year, but perfectly functional.
Includes a 10ft extension cable to help get it to the location you need it as well as mounting brackets.