Specification:Item Type: Electric Bicycle Hub MotorMaterial: Aluminum AlloyOpening Size: Approx. 170mm/6.69inWheel Size: 20/26inchMounting Position: Rear DriveSpeed: 430rpmSpeed: 35-40km/hTorsion: 85N.MBrake: Disc BrakePackage List:1 x Hub Motor 1 x Connecting Wire