[Fitment] This Daytime Running Light Controller fits for all Brand of cars. [Product advantages] Mini shape,light weight and waterproof, Time-lapse power off function . Constant light + dimming + delay + automatic switch. [Intelligent start up] When the car is started (the voltage must be higher than 13V+), the daytime running light is automatically turned on. When the headlights (or reading lights) are turned on, the daytime running lights are dimmed (darkened), when the car is turned off (the voltage must be lower than 12.5V) , the daytime running light is off after 15 seconds [Easy Installtion] Simple installation,with no need to change any electric line. [Note]After the battery is connected, the daytime running light will turn on for about 15 seconds and then turn off the light. This is a normal phenomenon (realizing the delay function). After that, you need to start the car. When the voltage reaches 13V+, it will start working Day Running S , Auto Led Day Running S Dimmer On/off For All Of Cars