Important NOTE: This item is for the bike that uses the hub diameter less than 36mm. This item does not include battery or charger. This is our newest kit for electric common bike, this kit mounts the sprocket on the wheel spokes, so it fits most of bicycle wheel. Motor use freewheel so when wheel rotating, the motor will not rotate, just like a normal bike, this can reduce resistance. The thumb kit includes: 1.1x 250W 24V brush motor with freewheel 2. 1x Customized sprocket, components 4. 1x Motor controller 5. 1x Mounting plate 6. 1x Wuxing thumb throttle (with battery indicator, switch button).