I got this replacement battery for my VX231 radio. Nick was very informative and helpful.
Vertex FNB-V131LI-UNI 1380 mAh Lithium-ion. This is the new style battery which now comes standard with the VX231 radios. It now has 4 connectors on the back which Vertex refers to as a "UNI battery" also known as "universal battery". Vertex made this change to 4 connectors (instead of the old style which has 3) to allow users with other Vertex radios to all utilize one charger. Two Way Direct guaranteed new Vertex Standard Original Product. For use with Vertex VX231 radios.