Yahboom 4 Channel Infrared Tracking Sensor Module For Smart Car Robot, Spec: With 6Pin Cable+23mm Copper Column1. This tracking module uses four tracking probes and optimizes the spacing layout. The two inner probes can precisely identify the black lines, while the two outer probes can assist the inner probes in identifying the black lines and provide warnings. The vehicle can recognize 90 degree turns and other complex road surfaces. 2. The knob type adjustable resistor is combined with a professional operational amplifier circuit, allowing the adjustment of