This is a tire pressure reset device, or in other words, a learning device.After each tire rotation, tire, body control module, and tire pressure sensor replacement, the sensor re matching program must be performed to ensure the accuracy of tire pressure value acquisition and display.Operation steps:1. Ensure that the car is in TPMS learning state/mode.2. Follow the car maintenance procedure, hold the instrument in sequence (left front, right front, right rear, left rear), align it with the tire sidewall near the valve stem, and press the green reset button.3. At this time, the green LED light (TX light) will light up, indicating that the signal is being transmitted. When you hear the car beep sound, it means that the matching is successful.4. Match the other tires in sequence, and the product will flash continuously to complete the matching of 4 tires at once. After successful matching, press the red power button to turn off the powerApplicable models:for General Motors, for Buick, for CadillacColour:OrangeMaterial:ABSPackage Contents:1 * Car EL-50448 II Tire Pressure Reset Activation Tool