Glass reflective spike good weather resistance, long life: Good abrasion resistance, good chemical stability; Capability of tires and sand abrasion; Resistant road surface may be encountered in various solvents, fuel rot; Acid rain and salt spray also has a strongresistance to long-term use in a variety of severe road conditions. Safe, reliable, and a warning: The glass spike is made of high-crystalline silicon reinforced optical glass coated with silver-white reflective layer, the reverse reflection coefficient of more than 300mcd/LX.