When the battery is low the device will flash red 10 times. While charging the battery indicator button light will change color based on the amount of charge. Red = 0-5%, Green = 5-50%, and Blue = 50-99%. Once the device has finished charging the button light will turn off
The blue light behind the button will not be lit anymore once it is fully charged. The device also shuts off once fully charged. Click the button 5 times rapidly to turn it back on.
While charging the back indicator light will indicate the level of charge, once fully charged the light will turn off.
During the charging process the light will stay red, once fully charged the light will turn green and stay on until disconnected from the charger.
The button light will flash red when low on power. While charging, the base light will be red, once fully charged the light will turn off.
Nitro2 and Cyclone:
The USB ego charger light will change to green once the pen is fully charged. It will display a red light if not fully charged.
NOTE: To extend the life of your battery do not leave on the charger once fully charged.