I work for a company Bike2Power, and we sell bicycle USB charger kits for smartphones and iphones called SpinPOWER Kits. It is a bike-mounted charger for USB-chargeable devices that uses a bicycle dynamo. Incidentally, our charger is now being tested by a RAGBRAI rider. If you are interested, please contact us and I will connect you with him so that you can obtain his feedback directly. So far, he is pleased with it and wants to take it to the RAGBRAI with him.
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