Originally Posted by jd666

I use it for two instances, to let the person know who i am overtaking, that i am overtaking him, by flashing my headlight behind him. And other when i dont have adequate road width ( or safe road width ), available, because the oncoming vehicle is overtaking another vehicle or too much on the wrong side ( mainly on a two way highway), to warn him that i dont have adequate space, and he should move back into his lane.