Description:  1. This is a commonly used Grayscale Sensor that uses a TCRT5000 reflective black and white line to identify sensor components. The principle of the sensor is to use the different reflectivity of infrared to color and convert the strength of the reflected signal into a current signal. When the sensor does not detect an object or detects a black object, the signal terminal is at a high level; when a white object is detected, the signal terminal is at a low level; its detection height is 0-3 cm. We can adjust the sensitivity by rotating the potentiometer on the sensor, that is, adjusting the detection height. Sensitivity is best when the potentiometer is rotated, which is the critical point between the D1 LED and the D1 LED.  2. The sensor is compatible with various microcontroller control boards, such as the microcontrollers. When using it, we provide a method for using this sensor with the microcontrollers.  3. The sensor comes with a 2.54mm anti-reverse plug white terminal. When in use, we can connect to the MCU with DuPont cable. To facilitate wiring, we specially designed an expansion board that is fully compatible with this sensor and the UNO R3 microcontroller. We only need to stack the expansion board to the UNO R3 MCU, and use a 3P double-head XH2.54 plug wire (anti-reverse) to connect to the expansion board, which is simple and convenient.  4. At the same time, the sensor comes with 4 3mm diameter positioning holes, which allows you to fix the sensor to other devices.     Specifications:  Working voltage: DC 5V.  Interface: 2.54mm pitch 3pin anti-reverse interface.  Positioning hole size: 3mm in diameter.  Control signal: digital signal.  Detection height: 0-3cm.  Size: 38*12*9mm.  Weight: 2.5g.     Package Included: 2 x Grayscale Sensor (the other items are not includes)