Specification:Item Type: Electric Bike Wheel Hub MotorMaterial: Aluminum AlloyWeight: Approx. 4900g / 172.8ozOpening Size: 170mm / 6.7inWheel Size: 20 or 26 InchInstallation Position: Rear DriveSpeed: 35-40km/hMagnetic Steel Pole Number: 46RPM: 430rpmTorque: 85N.MBrake: Disc BrakePacking List:1 x Electric Bike Wheel Hub Motor1 x Connection Cable