???? If you don’t use brakes with sensors you destroy wheel and after you can’t return the wheel back. Powerful Hub Motor: 27.5 48V/52V real 1500W in the pick its 1850W super power brushless gearless hub motor. Premium Materials: alloy rim & stainless steel spoke, Rare-earth metal magnates are used in the motor to efficiently produce large power. Drive system without moving chains or gears: No friction, more efficient, less chance to break. The brake shuts off motor automatically: Saves energy and improves safety. Size: 27.5 inches(Wheel size). Type: Bicycle Conversion Kit. Brake Type: Hand Brake. Wheel Type: Rear Wheel (27.5 / 48V/52V / 1500W). Power: 1500W/48V/52V or 250W/48V/52V. Spokes: Steel, 12G×0.1. Max load capacity: 551lbs. Electric Bike Part Type: Conversion Kit. Compatible Bike Type: Universal. 1x Brushless Gearless Motor Rear Wheel. 1x Intelligent Motor Controller. 1x Pedal Assist Crank Sensor. 1x Cable Ties & Plastic Coil. 1x Pair of Handle Bars (included Twist Throttle). 1x LCD meter SW900. 1x Pair of Brake Handles. 1x bag for controller. 1x 7 speed cassette. Battery and charger are not included in package.