Fog lights are designed to be used in fog, heavy mist, snow and other poor-visibility situations. They’re different from daytime running lights. They are an extra pair of lights mounted low on the vehicle, with the thinking that fog doesn’t settle on the road surface but hovers 12 to 18 inches above it. Located below the headlights, fog lights are designed to illuminate the road and emit a wide light beam that won’t reflect off of fog. Fog lamps are generally installed low on a vehicle and are angled downward to illuminate the road below the fog, helping to prevent any reflection that can affect visibility.