The Eton BoostTurbine Portable Battery Backup will never let your smartphone run empty. This hand turbine power generator features a rechargeable 2000mAh lithium battery, just enough juice to recharge your mobile devices. One minute of turning the hand crank of the Eton BoostTurbine Battery will give you about 4 minutes of talk time. You may not want to spend hours cranking the hand turbine, but The Eton BoostTurbine backup is perfect for emergency situations. Compact, light, and durable, the BoostTurbine fits perfectly at the bottom of your backpack, or stored away deep in your glove compartment. Be prepared for the worst and get your Eton BoostTurbine here.