there is a pair of infrared mitting and receiving tube of the IR sensor module, tube infrared emit a certain frequency, when the detection direction meets the obstacles (reflecting surface), reflected infrared receiving tube, after the comparator circuit processing, green indicator will light up, at the same time signal output interface to output digital signal (a low level signal) Function: the IR infrared obstacle avoidance sensor module can be applied in robot obstacle avoidance, obstacle avoidance car, line count, black and white line , etc. Adjustable distance: the detection distance of the infrared module is 2 to 30 cm, and the detection angle is 35 degrees, Easy to use: the output port OUT sensor module can be directly connected to the microcontroller IO port, you can directly drive a 5V relay Application: the IR sensor module can be applied for 3-5V DC power supply modules; There is a red power indicator<br><br>Colour:Blue Material:polymer<br><br>Package Contents: 10 x infrared obstacle avoidance sensor module<br><br>Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.