Description instructions: Unscrew the original gas Clean the dust on the threads and other places. Align the cap screws Screw on the tire pressure cap of this product. If it is not tightened or the tire pressure is insufficient, it will display red or yellow. Use a wrench to reverse the nut When the tire pressure is normal after tightening, it will display green Specification: Product Name: Tire Warning Product specifications: 4pcs/set Product material: copper core Product weight: 32g Product size: 10 * 23 * mm Product features: Tire pressure warning cap is a tire pressure aid used to measure tires. The tire pressure cap is locked on the tire nozzle and displays the color change directly on the transparent cover. Specification: Instructions for use: Normal: In the case of standard tire pressure, the transparent casement should be green and the vehicle is running normally. Warning: The tire pressure is slightly lower than the standard value by about 10%. The transparent casement is yellow-green and should be inflated in time. Danger: Tire pressure is about 25% lower than the standard. The transparent casement should be yellow. It should be checked and inflated immediately. If the tire pressure is reduced by 15%, your car will increase fuel consumption by 6% and double tire wear, which will increase the danger by 30%, and the upper tire pressure will remind you of this. The danger of insufficient tire pressure: The tires are very soft, the contact area with the ground is too large, and the fuel consumption is also increased. The contact surface of the tire is deformed greatly, and Lu Liangniang's inner curtain is fatigued long, which affects the service life. A larger contact surface will increase the likelihood of the tire. Lower braking performance will affect the operation of the vehicle. Package Included: 4 *Valve warning cover 1 * Wrench 4 * Nut Note: 1. The real color of the item may be slightly different from the pictures shown on website caused by many factors such as brightness of your monitor and light brightness. 2. Please allow slight manual measurement deviation for the data.