Known as Cable Barriers or Guide Wires, they're designed to prevent vehicles from veering off the highway and crossing into oncoming traffic. The video shows crash tests where these barriers stop vehicles weighing up to 18,000 pounds! ​Made of strong steel wire, these barriers are actually much more forgiving than traditional concrete barriers. Instead of an immediate, hard stop, the cable barriers safely redirect out-of-control vehicles back toward a safer path, preventing a potentially deadly