Bi-Directional Pavement Levelled Stud, also known as solar road stud light or road reflectors, are unique traffic safety warning lights installed along a road or motorway surface. Solar road stud lights as an energy-efficient universal traffic safety solution. The primary purpose of Bi-Directional Pavement Levelled Stud is to indicate the direction, especially in difficult rainy or foggy conditions and to remind drivers to pay attention to the driving course ahead.