Install Instruction:  1. Install instruction about the batteries: Put 3 pcs AAA(1.5V) batteries in  the battery case and install them according to the positive & negative as  marked in the case. Then close the batteries case.  2. Install instruction of the shadow light: Stick the Magnet on the bottom of  the car frame. Stick the car light on the car door. The distance between  the Magnet & Car light is about 10mm. When you close the car door, the  Magnet is at the under face of the sensor on the car logo light.  3. Automatic Control & Manual Control: When you open the door, the logo  will be shown on the ground, and it will turn off automatically after 2  minutes. If you want the light on/off, just need to press the button on the  head of the light.  One set includes 2 pcs, suggest you buy 2 sets for 4 doors of your car!