Describe: The material can store light, absorb the light source when there is light, and emit light when it is dark! ! ! Features: 1. Tire Valve Stem Covers: These tire valve stem covers are made of shiny rhinestone material. Give your car a unique luxurious look with a beautiful dazzling glow. 2. Universal Tire Valve Covers: These wheel covers help keep tire inflation at the proper level for bikes, cars, SUVs, trucks and other motor vehicles. 3. Tight leak-proof seal: Our tire valve is stuffed with rubber sealing ring inside, forming a tighter and more effective seal, so it won't leak during long and hard driving. 4. Easy to install - 4 stem caps, can be easily tightened by hand, no additional tools are required, very simple and convenient. 5. The cap size is 16*12mm. It is universally applicable to standard valves. 6. Prevent dust or snow in the valve from being easily corroded, and prevent foreign objects from blocking the valve core and causing the tire to leak and cause accidents Specification: Color: Green ,Yellow ,Blue ,Pink ,Red ,Orange Material: ABS material Size: 16mm*12mm*12mm/0.62*0.47*0.47in Package Included: 4pcs * tire luminous valve Notice: Due to manual measurement, please allow 1-3cm error, please make sure you don't mind before placing an order. Please note that there may be chromatic aberrations in the colors due to the position of the image. The longer the light absorption time is, the longer it shines