ProdecoTech v4.0 Mariner 500 48V 500W 9 Speed 9Ah Li Ion Electric Bicycle, Electric Blue Metallic, 20-Inch/One Size Folding Aluminum Frame Rear FSG 48V 500W Motor Continental Tires 20"X 1.75" Speed 20mph; Distance per hour 25-35 Miles Twist Throttle Control