I was very surprised when I received the spare additional batteries and charger I ordered for my new phone.  The batteries were clearly marked for use in my phone which was very nice.  The charger was a "universal" type.  That means that it is designed to hold many different types of batteries.  It also allows for various spacing of the contacts to mate with the battery contacts.  At first I did not think I was going to like the charger, especially with no instructions with it for my specific phone.

There are two pins on the charger and three contacts on the batteries.  The battery can be placed front or back forward, so polarity was an issue.  One clue was that after inserting the battery correctly, the indicator light goes on.  Another clue was to look at the O.E.M. charger to see that only the two outer pins are used (not the center contact), and the front of the battery faces out.

The batteries perform like the O.E.M. battery.  Overall the charger works well and considering the price is more reasonable than O.E.M. components, I would buy Anker products for my other devices.  I will need just batteries for the other devices because the universal charger can do all my various electronics batteries, and with a standard and micro USB charging port built-in, it can recharge my devices without having to remove the battery!