Specification- Overall Dimension(Dia.xW) 20 1/2" x 8 7/16"- Compatible Tire Size 24" x 2 3/8" to 3"- Rim Diameter 20 1/2"- Hub Length 7 7/8"- Rear Dropout Spacing 5 5/16"- Motor Diameter 7 7/8"- Spokes Length 6 3/8"- Spoke Screw Type 12G- Controller Power 750W- Controller Current andamp Voltage 26A 36V- Controller Size L17xW8xH4cm- Motor Speed 500 Rpm- Hub Torque 50 N.m- Compatible Battery 36V 15 Ah- Suitable Brake Type Disc / V-brake- Weight Capacity 220 Lbs- Net Weight 17 Lbs. Package Contents:- 1x Motor Wheel- 1x Controller- 2x Brakes- 2x Handle Bars- 1x Thumb Throttle- 1x Pas Sensor- 1 Set of Flywheel- 1 Set of Torque Arm- 10x Wire Ties- 1x Spoke Adjuster- 2x Winding Pipes- 1x Controller Bag. Notice: - Battery, charger and tire are not included, please prepare them before using.- The electric wheel is only applicable to conventional bicycles, not for tricycles, tractors, etc.- Please go to automobile repair shops with standard business license for modification.