Traffic cones, also called traffic pylons, road cones, highway cones, safety cones, construction cones or (colloquially) witches' hats or safety wizards, are usually cone-shaped markers that are placed on roads or footpaths to temporarily redirect traffic in a safe manner. They are often used to create separation or merge lanes during road construction projects or automobile accidents, although heavier, more permanent markers or signs are used if the diversion is to stay in place for a long period of time.

The Manual of Uniform Traffic Control Devices (MUTCD) limits the use of 18" traffic cones, when used on public roadways, to daytime hours and low speed (40 MPH or less). The 18" traffic cone can be used freely in non-public roadways or for foot traffic. Typical non-public roadway and foot traffic applications include parking garages, parking lots, racecourses, carnivals, shopping malls, etc. Weighing only three pounds each, the 18" traffic cone is ideal for large events requiring the use of several cones.

The MUTCD classifies 28" traffic cones for night time and/or freeway and highway use, where speed limits are 45 MPH or greater. The 28" traffic cone commands much greater respect from motorists, and weighing 7 pounds apiece, they do not get blown over as easily as the 18" traffic cone. These two features make the 28" traffic cone much safer for all roadway applications. For nighttime use the 28" traffic cone comes equipped with 2 reflective collars. These reflective collars are made of the same Hi Intensity reflective sheeting used for barricades and signs.