RF-Nano Arduino
$ 3.00
The RF-Nano is an Arduino Nano with built-in wireless connectivity. It's the brain of all Candle devices.
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Need more range?
You can also combine these three parts to create an RF-Nano alternative. It's a good choice for the Candle Receiver. You'll have to uncheck "RF Nano" when you upload code to it via the Candle Manager.