Ubiquiti NBE-M2-400 NanoBeam M Quick Start Manual page 4

Release Button
Release button; it should be fully engaged in the Release Button
Slot of the Rear Housing. This ensures that the Antenna Feed is
locked into place. If you need to remove the Antenna Feed, you
must depress the Release button first.
LEDs
Signal In airOS, you can modify the wireless signal
strength threshold values for each LED on the
Advanced tab under Signal LED Thresholds. The
LED will light green when the wireless signal
strength is above -65 dBm.
LED will light green when the wireless signal
strength is above -73 dBm.
LED will light amber when the wireless signal
strength is above -80 dBm.
LED will light red when the wireless signal
strength is above -94 dBm.
Ethernet
when an active Ethernet connection is made and
flash when there is activity.
Power
device is connected to a power source.
The Ethernet LED will light steady green