A:AnswerThis is the "Sessions" model the other is "Black".
The main difference being:
1. Size (this one is smaller) and thus makes it a little bit more versatile
2. No LCD Touch Screen in the back (hence why its smaller).
That's what makes this one cheaper.
A:AnswerI called GoPro about this product last week and they said it has a built in battery. Depending on use (pictures, time lapse, or video) the charge will last for about 1.5 hrs of recording.