Usage Tips:[High ] The wires and interfaces have good contact to low malfunction for long time use. Meanwhile, the over/under voltage protection, over current protection, over load protection, over heating protection, anti-runaway protection, locked-motor protection make this kit safe and reliable. [Labor-saving] You don't have to pedal your bike laboriously anymore with this product and only need to gently rotate the turner to control the speed flexibly, which is very labor-saving and convenient. [LCD Display] The LCD meter with color screen can clearly allowing you to grasp the usage statues of the product. Meanwhile, backlight enables you to see screen clearly in dim environment. [Wide range of applications] The controller is a sine wave three-mode controller, matched with Hall and non-Hall brushless motors, with self-learning function Applicable to 36V1500W 36V2000W 48V1500W 48V2000W 52V1500W 52V2000W brushless motor Hall and without Hal [Protect ] XT60 plug. This plastic box is made of Insulating material, not easy to burn, fireproof, accurate Keep battery safe Three-mode controller prevents motor reversal If the motor is running in reverse, just connect the two pull wires can be pulled out so that it can be rotated forward,No need for long-term connection. Two speed limit lines are connected together and inserted into each other , you just need to unplug the plug Turn it on to release the speed limit. Colour:As Shown Material:Plastic+Metal Package Contents: 1 * Controller 40A 1 * Instrument Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.