The device is designed for places with poor 4G reception. With the task of distributing mobile Internet to several devices, it copes perfectly. The kit includes two external antennas. It's not clear why, though. On the built-in antennas, reception is more than confident (mobile Internet speed on a smartphone is 1 Mb, on a router 7 Mb). I did not find any difference in operation on external and internal antennas.
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