... , planetary gears, noiceless, powerful, small volume, light weight.Operation: Pedal AssistPedal assist work automatically when you start pedaling. The motor ... assistance will come on to assist you when you pedal. It will make pedaling really easy, you will ... or press the brake.S300-1Including following DIY E-bike parts: Model No.98SWXDC3398SWXC33Motor with controller insideDisc brake motor ...