Affected by light source and power supply, there is hidden danger for the airport runway signs of most countries.To solve the problems, after years' of research and development, our company has succeed in bringing out special glass beads which can be widely used for airport runway and high grade roads, the refractive index of which is up to 1.9-1.93. The combination with hot melt marking paint can absolutely meet the requirement that pilots can see runway marking signs at night clearly. It is a ideal reflective marking material for airport runway and high grade roads.