Foreverbattery KA710 Wind-up Dynamo Rechargeable 5,000 Mah USB Emergency Battery Pack/Charger for Cell Phones and Other Mobile Devices, 17w High Capacity, 5000mAh; Add 3 full charges or 20 hours of talk time to iPhone 5 / 4S / 4 / 3GS, 2 full charges for Samsung Galaxy S3, or 200% + to most mobile phones' battery life Charging: USB 5V DC including USB cable & wall charger + Hand Crank Built-in super-bright 1 Watt LED Flashlight 4-LED battery strength indicator High-quality Lithium Polymer battery lasts 500+ charge cycles