IR Encoder Speed Motion Sensor Module (4-pin) for Arduino

Features
Use imported groove coupler sensor.
Groove width:5mm.
Output state indicator lights.
Obscured output high; unobstructed output low. 
The comparator output, the signal is clean, the waveform, driving ability, more than 15mA.
Operating voltage 3.3V-5V.
The output in the form: Digital switching outputs. (0 and 1) 
A fixed bolt hole for easy installation.
Small plates PCB Dimensions: 3.2cm x 1.4cm.
Using a wide voltage LM393 comparator.


Reference Link:
https://brainy-bits.com/tutorials/speed-sensor-with-arduino/

#Sensor