This small, palm-sized battery power meter has a small display that shows off how much juice is left in your single Lithium Ion/Polymer rechargeable battery. The color display has four levels of power indication once battery capacity becomes 100%, 75%, 50%, and 25%. When power is below 25%, only the red battery frame lights up.

The design is pretty basic, it's just doing basic voltage comparisons, and of course, it will drain any battery it is connected to - but for beginners, this is a pretty easy way to check single 3.7V/4.2V Lithium Ion or Lipoly batteries.

Comes with two bare wire ends, connect black wire to ground, red wire to positive - check your battery for the polarity because batteries not from Adafruit may have a different connector setup.

Note: PCB may come in green or blue. Battery not included.