1. First, press and hold the red button in the middle for more than 10 seconds. At this time, the infrared thermometer will automatically restore the factory settings.
2. Then start to set the calibration, first turn the infrared thermometer to the side, you can see that there is a groove on the side.
3. Then push it hard to the right with your hand or a screwdriver to open it.
4. After opening, you can see that there is a temperature selection switch on the battery compartment inside (the default ℃ here).
5. Turn the switch to "°F", and the temperature display unit has been set to Fahrenheit at this time.
6. After closing the battery cover, you can see that the temperature display has been switched to Fahrenheit on the display, and the calibration is complete.