A Puck that is configured as a "Sensor".
A Sensor Puck reads temperature, and humidity, and can send IR commands to a paired IR device (mini split, window AC, portable heaters, etc.)
A Sensor Puck can be powered by two AAA batteries or plugged into AC power using the supplied USB cable and adapter.
A Sensor Puck will briefly connect to WiFi when downloading a codeset for an IR Device it's paired with or when receiving a firmware update. Otherwise, Sensor Pucks are not connected to your home WiFi and communicate directly with a Flair Bridge or Gateway Puck using the 915 MHz Flair RF network.