This newly developed advanced line finder kit is very easy to use. Come with 5 pairs of IR transmitter and receiver, it can covers line detection detection distance from 1: 4 cm and line thickens from 1: 3 cm. Above all, it has auto-calibration capability (this means you can store the line color you want to detect in the line finder internal non volatile memory) The line finder detect dark color or bright color line. With 1 press, it will start "recognizing" the surface under it, calibrating the threshold between dark and bright. it takes 4 to 5 seconds only. After that, it is done, being stored in internal non volatile memory, it will still "recognize" the line even after power off and on again. Come with connector and wires. Kit Includes: Line finder module Connecting cable Features 5V power 5 digital output representing logic of 5 IR sensor 1 press to start calibration 2 press to toggle logic into Dark On mode, to sense dark line 3 press to toggle logic into Bright On mode, to sense bright line Calibration button for easy of calibration Specifications Input voltage: 5v Detection distance: 1:4 cm Line thickness: 1:3 cm Number of sensors: 5 (5 IR transmitters + 5 IR receivers