Insert the cigarette lighter plug into the DC 12V jack in the car, and then start the car. 2. Three-meter long power cord for easy connection to front and rear tires. 3. Screw the inflation nozzle onto the tire that requires ventilation. 4. Button description: R key is a unit conversion key;-key is a minus sign; + key is a plus sign key, any press-or + key to enter the preset mode. 5. If you want to set the adjustable button on,-key is off). 6. After setting the default value, wait 3 seconds, leave the preset mode, and detect the current air pressure in real time. 7. Suction the set value upward and stop the pump automatically. 8. When re-inhaling, you need to turn off the switch and then turn it on again to start absorbing water again. 9. Car air pump, continuous working time should not exceed 8 minutes, and need to rest