Description: Double Protection: Fluorescent tire valve stem cap is protected by luminous plastic insert and transparent shell, a good valve cover will extend the service life of the tire. Luminous Design: Tire valve stem cap inner layer is designed with luminous material, which can be used to decorate the tire valve stem cap light at night. When the wheel starts moving, it will automatically flash and form a halo, making your car, motorcycle, bike look beautiful. Wide Application: Luminous auto wheel air valve cap, 7mm inner diameter, 13.8mm inner diameter tire valve stem cover, suitable for cars, bicycles, SUVs, trucks, bicycles and motor vehicles, etc. Easy To Install: Glowing tire valve stem caps internal protection adopts a rotating thread design, which is convenient for manual tightening during installation. Note: Since fluorescent materials need to absorb light sources, they will glow at night. Does not absorb light when stored in airtight packaging for long periods of time. Before using fluorescent lamps for the first time, light them with LED lights or leave them in sunlight for 5-15 seconds. Specification: Material: Plastic Product Size: Outer Diameter 10mmx10mmx15mm Package Includes: 16Pieces Luminous Auto Wheel Air Valve Caps Note: Please allow slightly errors 1-2cm differences due to manual measurement.