Detailed Description  Sizes 28×54cm 28×55cm 26×50cm 24×43cmRear Derailleur: Aluminum Alloy 1/2×1/8×42T  Speed: Shimano KSG3R40A-3-speed internal Lights; Dynamo Sestem 6V Front-2.4W,Rear-0.6W Motor Rear Hub36V250W (brushless) Maximum Speed: 25km/h Battery: lithium-ion 24V/9AH Charger DC24V1.8A AC110V-240V Range Per Charge: 28-50KM, 26-45KM 24-40KM (varies depending on terrain, rider weight and riding style) Charge Times: 3-5hrs, full charge Weight: 20-26kg,,  Tires: made by America factory brand (CHENG SHIN TIRE)