When you're in a bind and your battery drops to low, power up with the Goal Zero Guide 10 Plus Solar Recharging Kit. For MP3 players, GPS, cell phones, etc., you won't be out of luck should your battery run out. Keep your AA or AAA batteries going strong using either the sun or any USB port. You can directly charge a Smartphone in one hour. The built-in LED light runs for 150+ hours per charge. Unfolded: 9"H x 17"W x 1.5"D. Folded: 9"H x 6.5"W x 1.5"D.