This Hand-Crank USB charger is designed to energize any phone or USB compatible device in case of emergency or lack of power.</br>Maximum Output Voltage: DC 6V</br>Maximum Output Current: 300 mAh</br>1 Minute Charge= 3-5 Minutes Talk-Time</br>You can also turn this into a flash-light by simply inserting a USB light.</br></br>Product Description</br></br>This Hand-Crank USB charger is designed to energize any phone or USB compatible device in case of emergency or lack of power. All chargers are sealed in 100 % Waterproof & Airproof mylar pouches to preserve it until needed. This pack will survive through even the roughest Rafting Expedition. Its small?? compact design makes it ideal for any purse?? back-pack?? and/or glove box. Test results show that this charger works with almost all phones including smart phones and USB devices.This device will only charge your cellphone when the battery is below 3.5V (or 10% of its charge)?? and it will only bring it to around 10%?? no more. If attempting to charge a partially charged phone it will discharge your battery instead of charging it. You must crank for 20-30 minutes for most smart phones to get an emergency charge. These results show longer charging sessions maybe necessary with some I-Phones?? I-Pads?? and other products that have large battery capacities. SOS Hand-Crank Chargers can be a life-saver in those situations where power is unavailable. Why pay for those over-priced