Snap-On Traffic Cone Signs give directional reinforcement in the work zone. In addition to use on traffic safety cones, they also can be used on Barrels and Delineators. Supplemetal standard warnings and directions create a safer work environment. The signs are made of durable, reusable, all-weather plastic with UV inhibitors for maintenance of color. These signs were developed through research by the Federal Highway Administration to improve safety and reduce liability. Proven effective, they are used by more than 2000 cities and utility companies.