Studs have been designed and manufactured to withstand particularly difficult environmental and traffic conditions. The aluminum alloy used offers maximum impact resistance to vehicular traffic and spreads the impact load unformally over the pavement surface. They are manufactured from aluminum ingots complying with BS 1490. The stud has one or two prismatic reflective faces as required to reflect incident light from a single directions or from both directions. Reda Aluminium Road Studs have a patented anti-twist shaft design to provide anti-torque movement of the stud whilst in service. They are affixed to the pavement surface by means of a hole drilled into the surface and filled with Reda Grouting Material in molten state prior to insertion.