Energy source that powers phone anywhere, anytime. Ideal for business trips, the outdoors, hiking, boating, fishing, camping and promotional purpose. It need no power source. Just rotate the handle and it will act as an charger for mobile phone. Cranking for 3 minute can gain 3-8 minutes mobile phone talk time. LED light built in. Compact size and light weight for easy carry High quality dynamo and long life components Works on most mobile phone in the market Safe design Support charging the interface of all mobile-phones on the market(Customize according to the request of you)