As a volunteer first responder I use these lights not only to warn drivers that there's an accident I'm working,they also helps the ambulance and other emergency personnel find me if I'm not sure exactly where my location is, they also warn drivers to slow down when I'm assisting someone with a disabled vehicle,the lights are very bright and well worth the money spent good quality products, installation is fairly easy but it is a little time consuming as well. the only negative thing I have suction cup has to be softened up with hot water or use pliers to get them through the bracket and if you want them to mount level on your windshield, rear glass etc you have to have them turn the same way meaning you can't have the red on the right on one bar and all the way on the left on the other bar. Other than that the lights are great investment.