How to make Reverse Polarity Protection Circuit

Hey there this video is going to be on reverse polarity protection because if you made any circuit 5v/12v and connect with wrong connection then they burn or not works.
To protect your circuit you can definitely use diode it protects in reverse bias but it drops voltage from 0.3v to 0.7v this lead loss in high current opration so I use relay for that job and it worked very well.

Here the circuit Diagram :

Components used :
1)5v/12v Relay
2)Red & Green led
3)IN4007 diode
4)1K resistor