Devices IN
Device IN is where you pull data from. That is, the device's data.
Here you can, among other things, use name to put in dashboards and create some columns if you have several different units in the same dashboard.
Regarding “IN”, pay attention to what is stated in the product manual.
Button is the physical button on the box that you can code into your flow.
Signal is a readout of signal strength – typically between 0-30.
Last Update when was the last update.

Devices OUT
For Devices out, there are several different options – this also changes based on the product.
If there are things like “buzzer” and “LED”, you can, among other things, stop the buzzer and show light when the button is pressed throughout your flow.
