Dark Energy Reservoir
There are hundreds of portable recharging units on the market providing one recharge for your mobile phone, but what good is that when you are out on a 4 day hike in a National Park? Dark Energy Reservoir is about the same size as their competitors, but it has one tiny difference. It recharges your phone up to 6 times. You could stay out on the trails for a full week and still have a charge on your phone when you climbed back in your car to drive home. Think about your digital camera that always goes dead on your hikes. If it can be recharged via a USB cable the Dark Energy Reservoir can recharge it up to 7 times, making sure you never miss those great shots.
The Dark Energy Reservoir might be slightly more expensive at $129, but you get 6 times the portable charging power. If you want to really be prepared, double your order for $249.