There are many USB battery backup devices but not all have the features that you really need, this Techlink is small portable and delivers the power when you need it, even keeping a charge for up to 3 months, if you need power on the go then this is the device you need.The Recharge 2500 is a portable USB charger with the latest Li-Polymer battery technology built-in that will fully charge most smartphones and many USB devices whether you have access to power or not.The Recharge 2500 is pocket sized, lightweight and easy to use - just connect your USB charging cable to the built in USB port and press the Power button, charging will start instantly! The 2500mAh built in Li-Polymer battery will fully recharge your device"s battery, useful for when needing to make a call, watching films or playing games on your smartphone. Recharging the Recharge 2500 is easy. Plug it into any USB Powered Adapter, Car Charger or Computer terminal and the LEDs will instantly light up. Once charged the ReCharge 2500 will remain fully charged for up to 3 months so perfect to keep with you at all times. Use the supplied Neoprene pouch to store and protect the ReCharge 2500 and charging cable whilst in a bag or jacket so it is with you at all times. Pack includes:0.2m Micro USB 2.0 CableNeoprene Travel CaseInstruction ManualRecharge 2500 unitTechnical Battery Power: 2500mAh Surge Protection 1.0amp Charging High Speed USB Charge Indicator