Luminous Valve Caps Fluorescent Green Blue Night Glowing Car Motorcycle Bicycle Wheel Styling Tyre Hub Luminous Cap Six Color BEFORE USE- How to test the fluorescence effect? Two ways: 1.Put it in the sun for serveral hours, and you can see the fluorescent effect in the dark place. 2.Irradiate the valve with the strong light of the flashlight for 15 minutes, and you can see the fluorescent effect in the dark place. The fluorescent valve can be reused. The longer the light is absorbed, the longer the fluorescent effect lasts. Note: This product is added with phosphor. It must absorb all kinds of visible light energy and store light energy before it can automatically light up in the dark. Buyers who do not know how to use can contact customer service after receiving the goods. About this item: Tire stem valves caps; Our valves caps are made of ABS, can light in the dark and protect the valve, prevent the water, dust or sand into the tire; preventing the valve from leaking, ensure the safe driving. Easy to install: 4Pcs luminous valve stem caps can easily tightened use your hand. Beautiful appearance, fits vehicles of various colors. Wide compatibility: Universal size fits more cars, bus trucks, SUVs, motorcycle, bike or bicycle. Perfect gift: The luminous air caps cover is made of durable ABS and luminous powder that glows in the dark and looks very sleek and stylish. It s the perfect gift for friends, bosses, family and more. Happy time: Imagine how happy it is for your car to use our luminous valve caps to shine brightly in the dark. Specifications Material: ABS Plastic, phosphor Color: Green, Red, Yellow, Blue, Pink, Orange Size: length(1.6cm/0.6inch) Inner diameter(0.8cm/0.3inch) Outer diameter(1.2cm/0.5inch) Package include: 4Pcs/8Pcs/16Pcs* Luminous Valve Caps