NB-IoT2 Unit, what is it, and are there any existing firmwares using it?

[A Former User]

Hello all. I've been playing around with the Cardputer and some M5Stick devices over the last few months, both running existing firmwares and making some C++ apps of my own.

I recently went on a purchasing spree for add-ons and picked up the IR receiver, GPS, RF433 Tx & Rx, GPS and Lora modules, all of which I understand their usage. However, on the site I also saw something called the 'NB IoT2' unit, and since it was only ~£15 and wouldn't cost extra in postage, I threw it in the basket as well.

To be honest, I'm a little bit stumped, as I'm not really sure what I've bought. Can anyone shed any light on what this unit is used for, or suggest any existing firmwares (or even libraries) that use it?

Item description can be found on the M5Stack site, which I've read, but I'm still none the wiser: https://docs.m5stack.com/en/unit/Unit NB-IoT2(SIM7028)