Description: brand new and high quality Features: The product is brushless dual-mode for smart measure battery voltage, motor phase. Powerful start, climbing power large and small motor noise. When the battery voltage become lower, the current will also become lower to keep normal running. It not only protect the battery and extend the battery life, but also increase the running distance. Automatically recognize the motor phase angle and motor right spin direction. It can be conducted by the Self-Study wires. Start silently, balanced and constant power out-put, Mature Production technical of Controller and authentic quality. Over-heat for protection, the controller will cut the power when the temperature is overtop, and restart if the temperature is normal. Intelligent management of battery system, the controller will reasonable control the battery discharge, low-voltage for protection function to extend the battery life. When overload of the bike to make the motor stall more than 2 seconds, the controller will cut off the current out-put to protect the motor and battery. Double-Mode, controller can check the motor hall sensor condition automatically. If the motor sensors are broken, controller will operate to None-Hall mode. When the motor phase is failure, controller will protect it, avoid motor burned, and protect the battery at the same for time. Instructions: Connect the learning switch. Connect the motor wire(phase A, phase B, phase C). Then connect the hall plug. Connect the power and the twist grip plug. Twist the grip plug. If the motor rotate reversely, cut off the learning switch, then connect the learning switch again. If the motor doesn'for t rotate, check the wiring. If the motor forward rotation, go to step 5. Keep the motor working at least 1 minute, cut off the learning switch. Twist the grip plug. If the motor works normal, connect other wire. If not, adjust the twist grip wire, until the motor works normally. Specifications: Color: As Pictures Shown Size: app.22.8cmx8.3cm/8.98inx3.27in Voltage: 48-72V Wattage: 1500W Throttle : 1.1-4.2V Undervoltage for protection : 41.50.5V Quantity: 1 Pc Note: Transition: 1cm=10mm=0.39inch Please allow 0-1cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you Motor Speed Controller only, other accessories in the picture are not included. Package includes: 1 x Motor Speed Controller