Use the power of the sun to charge your portable handheld electronics. To charge the built-in lithium battery just open the cover and face it toward the sunlight. It will be fully charged 5-8 hours later, depending on the intensity of the sunlight. The unit also can be recharged in any electrical outlet using the included AC power adapter. Once it is charged you can close it and take it anywhere to power compatible cell phones, MP3 players, iPods, GPS or any portable device with a 9-volt or USB connection. It also has a built-in LED flashlight that's great for emergencies. Includes multiple power adapters.