Features: Brand new and high quality The automatic solar panel tracking sensor has two ports, including power +/- and motor for M. Package List: 1 module, 2 probes. Principle: A protective cover is placed on the photoresistor. When light hits an obstacle and forms a shadow, the photoresistor on one side differs from the other side, and the motor is controlled to find a balance point, which is the center of the light source. It is recommended to use a geared motor. The lower the speed, the better the effect. The 5-5.5V regulated power supply cannot be directly connected to the solar panel. When the motor is connected to the circuit board, there is no difference between the positive and negative poles. During testing, if the motor's direction and the light source are opposite, reverse the motor wiring positions. Specifications: Material: ABS Weight: 28g Size: 35x16mm/1.37x0.62inch Note: 1.Please allow 1-2cm error due to manual measurement, please make sure you don't mind before ordering. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item. Package Includes: 1x Solar Tracking Module