Customer Rating: 



Summary: Works great, and has dual purpose
Comment: Keeps my second battery ready, instead of having to charge one and then the other in my Blackberry.
Also lets me charge my MP3 (or my phone) via the USB port (with applicable USB cable).
Only minor drawback is the position of the mini USB port(power-IN) and the standard USB (power-OUT to second item) are right next to each other, and my phones car charger (with the mini USB) is "L" shaped and interferes with the power-OUT port.