Yellow delineator for one-way tunnels, diversions or narrowings

The image shows a yellow vertical delineator, a supplementary device placed at the side of the carriageway. It is used along the sides of one-way tunnels and may also highlight a temporary diversion or a narrowing of the carriageway. It does not indicate a closed road, divide the carriageway into lanes or serve as a level-crossing countdown marker. Its visibility comes from reflective material; it is not internally illuminated.