Feature:1. Wide applicability can be installed in the front fork back fork between 15-41 mm diameter all of the bike.2. Portable size,easy install3. Energy conservation and environmental protection.4. Speed at 5-30 kilometers ,wil produce 100-1000Ah electric power5. Double USB output interface,4 Style Single Light to Remind the ElectricitySpecification:Item Name: Chain Type Bicycle DynamoSize: 80 x 50 x 80mmBattery Capacity: 1000mAhStandby Current : Output power: 5V/1AWorking Temperature: -10 -40 degreeincludes:1 x Bicycle Generator About Shipping: All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances.Any questions, please feel free to contact us During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours, wish you a happy shopping Thanks for your cooperation and we'll make you feel satisfied.