Does exactly what it says, only needed to charge my iPhone every other day for a week whilst snowboarding, might even use it in the UK in the winter! Really does extend the battery life and offers a great case to keep other things, money etc when you are in the slopes.
Great product, really competitive price, Eastpak products are built to last. The two zipped sections allow you to keep clothes separate and trolley handle allow for easy manoeuvre. I have the larger size also a weeks holiday, would recommend this if you are not wanting a rigid case, this offers a balance between hold all and case.