Description: It is easy to install the LED valve cap on the automobile wheel, which is a good decorative ornament and night protection equipment. Due to LED valve cap, your automobile will be more fashionable, and the bike can be easily found by vehicles driving far away at night, which reflect a good warning effect. It is constructed of PVC, alloy and LED material. The length of this product is 1.7cm and the height is 3.7cm. It is suitable for kinds of vehicles such as automobiles, cars, buses, trucks, bicycles and motorcycles. French valve is not available. Item Name: Valve Cap Material: PVC, Alloy, LED Features: Luminous, Tires Accessories, Decorate Battery: 3 x AG10 Button Batteries for Each LED (Included) Size Details: LxH: 1.7cm x 3.7cm(Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. 1. When installing, please align the positive and negative poles correctly, and the end without words faces the spring. 2. Be sure to put the battery in the black insulating holster inside, do not expose it, otherwise the battery will be short-circuited with the metal of the lamp housing, which will cause the battery to discharge and heat up, and it will be dead in a few minutes. 3. Be careful when twisting the lamp head, and make sure that the metal strip in the gap on the edge of the lamp head is in good contact with the metal base. (if the metal is too close, you can manually pull it out a little, but it must be careful!) 4. If it does not light up under normal conditions, you can adjust the length of the spring to ensure that it can fully contact the battery (do not use too much force, it is easy to cause the spring to fall off), if it still does not light up, go to step 3. Package Includes: 4 x Valve Cap Lights