The Levin Giant+ Solar Rechargeable Portable Battery Power Pack has a solar energy technology, environmental friendly and could recharge itself under sunshine for emergency purpose when outside. The Levin Giant+ Solar Rechargeable Portable Battery Power Pack can full charger your iPhone for emergency after being solar charged for 7hrs to 8hrs under normal sunlight. It has a Water resistant design that ensures the device functions smoothly when it’s raining. The Giant+ Portable Battery has a shock-proof feature that ensures the device working properly even it crashes or drops.The Levin Giant+ solar rechargeable portable battery power pack is perfect for hiking,camping and other outdoor activities.