Bike Conversion Part: This brushless gearless hub motor easily converts your bike into an electric bike, can be installed on a 20 to 28 inch bike. Low Noise: The noise grade of this bike brushless hub motor is ≤55, allowing you to fully enjoy the fun of cycling. [IP65 Waterproof: Featuring IP65 waterproof rating, this bike hub motor can adapt various cycling environments and harsh weather conditions. Strong Bearing Ability: The wheel hub is made of aluminum alloy and undergoes fine processing, w