What does that light on my charger mean? Do I need a new battery?

There is a color coding chart on the bottom of the single radio charger, and on top of the six-slot multi charger. This post gives you some additional information on what those indicators mean to you.

Also, check out this page for additional information on chargers and batteries:
http://brics.butlersheriff.org/help/radio/batteries-and-chargers/

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