It works in Europe too. It uses LoRa (A Long Range radio protocol) to be able to send messages out to other nodes, which can bounce them out to further nodes. A node can be configured to relay through the Internet to reach people in other areas.

I ordered the radio shown below from a kit on Amazon (it’s a Heltec v4 and came with a battery that isn’t pictured) and it took about 5 minutes to setup. Attaching the antenna to the board was the hardest part.

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