Motorway reflective stud placement
Motorway or dual carriageway reflective studs (or cat's eyes as they are also referred to) are designed to be most effective in poor light conditions by reflecting light back to the driver to signify which part of the motorway they are driving on, or where they might need to exit.
The colour of the studs always has the same placement on motorways and dual carriageways.
Questions relating to reflective road studs are often asked during the theory test.
Cat's eyes colours
Red motorway studs are placed along the hard shoulder of both motorways and dual carriageways. They can also be seen on the left of certain A or busy B roads.
Amber motorway studs are placed to the far right, running alongside the central reservation.
Green motorway studs indicate where a junction either joins or leaves a motorway, often called a motorway slip road.
White motorway studs are placed between the lanes of dual carriageways or motorways.
Blue motorway studs can occasionally be seen and are for the use of the emergency services.