Controller housing: The controller housing is made of high quality metal with a recessed design to protect the internal circuitry from thermal overload. High performance: Easy to install and use, with wiring diagrams to constant speed and sensitive and commutation control. Area of application: Our 48V 21A controller is suitable for the Cool Dog type of 10inch electric scooter, offering good compatibility for everyday use. Responsive control - Brushless motor control provides constant speed and responsive control of and direction changes for a satisfying experience. Easy to use - Our brushless motor controls for electric are easy to install and use, without adding to your burden or causing additional energy waste. Colour:Silver Material:aluminum alloy Package Contents: 1 * electric skateboard controller 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.