Description: Instructions Unscrew the original gas Screw on the tire pressure cap of this product, it will show red or yellow when it is not tightened or the tire pressure is insufficient. Green when the tire pressure is normal after tightening specification: Product Name: Tire warning Product specifications: 4 / set Product material: copper core Product weight: 32g Product size: 23*10mm Standard tire pressure: 2.4bar Product features: Tire pressure warning cap is a kind of tire pressure aid for measuring tires. The tire pressure cap is locked on the tire nozzle and directly shows the color change in the transparent cover. Specifications: Instructions for use: Normal: In the case of standard tire pressure, the transparent window should be green and the vehicle is running normally. Warning: The tire pressure is slightly lower than the standard by about 10%. The transparent window is yellow-green and should be inflated in time. DANGER: The tire pressure is lower than the standard by about 25%. The transparent window should be yellow. It should be inspected and inflated immediately. If a tire pressure is reduced by 15%, your car will increase fuel consumption by 6% and double tire wear, which will increase the risk by 30%, and the tire pressure cap will remind you of this. The hazard of insufficient tire pressure: The tires are soft and the contact area with the ground is too large, and the fuel consumption is also increased. The deformation of the contact surface of the tire is large, and the fatigue of the inner curtain of Lu Liangniang is long, which affects the service life. Larger contact surfaces increase the likelihood of a tire. Low braking performance affects the operation of the vehicle. Package Included: 4 X Tire Pressure Monitor Valve Stem Notes: Due to the difference between different monitors, the pictures may not reflect the actual color of the item. Compare the detail sizes with yours, please allow 0.5-1cm error, due to manual measurement. Please leaving a message before you give the bad feedback, if the products have some problems. Thanks for your understandings