Built tough for use as a weekend hike bag or as a large day-pack, this Solar Charging Backpack will provide your next outdoor adventure with an unlimited backup power source. The 2200 mAh battery pack can be quickly charged by a 2.4w solar panel in only 8 hours, making it the ideal emergency power supply for your electronic devices. You can even fully charge the battery with DC power in only 2 hours at night when there’s no sun light.