How do they make the front lights in some cars to alternate when they flash?

You know how in some cars, when someone turns on the signal lights left or right, the ones in the front alternate when they flash. There usually is one on the front and another on the side. Well, it flashes like, front, side, front, side, front, side and keeps alternating until it is shut off. How do they make this happen? Do they use a regular flasher? Combination Flasher? or what do they do? THANK YOU! I REALLY NEED THIS TO BE ANSWERED!How do they make the front lights in some cars to alternate when they flash?are you talking about the front amber light going on then the side marker light going on? This is built into the manufacture of the car. you may be able to talk to someone at an autoparts store and maybe get a relay.... usually it is vehicle specific.How do they make the front lights in some cars to alternate when they flash?it sounds like you're talking about the wig-wag switch used on police cars on their headlights. you could get a switch at some parts house and install it on your parking, or turn signals.(you may get in trouble if you do the headlights) they should come with directions on how to. if you're talking about one front and the side light flashing at the same time,it's because they are on the same wire and flasher.