Feature: The controller shell is made of aluminium alloy, which can protect the inner circuit and good for heat dissipation to avoid thermal overloading. This item is a brushless motor controller, it can provide steady speed, silent working, sensitive control of braking and direction changes. More efficient and more energy-saving. It can automatically identify the phrase angle and rated voltage of electric bike. The wires and interfaces are durable, and ensure low malfunction of long time use. Each interface has different color for your easy installation. Suitable for electric bicycles, scooter, etc. Specification:Material: Aluminium alloyOptions(Rated Voltage): 24V; 36V; 48VUnder-Voltage Protection: 20V/31V/42VRated Power: 800WMax. Current: 38APhrase Angle: 60°/120° (automatic identification adaptation)Size: Approx. 178 * 84 * 44mm / 7 * 3.3 * 1.7inchCable Length: Approx. 15cm / 5.91inchWeight: Approx. 680gPackage List:1 * Controller