Parameter setting: 1. Press and hold the [SET] button for 2 seconds, 24 hours flashes, press the [ALTI or and] button to switch between 24 hours or 12 hours 2. Press the [SET] key to enter the hour setting, at this time the hour number is flashing, press [ALTI or and] or [-] to set the hour value 3. Press the [SET] key to make the minutes blink, press [ALTI or and] or [-] to set the minutes 4. Press the [SET] key to make the number of the calendar year flash, and press the [ALTI or and] or [-] key to set the year value 5. Press the [SET] key to make the number of the calendar month flash, and press the [ALTI or and] or [-] key to set the month value 6. Press the [SET] key to make the calendar date numbers flash, and press the [ALTI or and] or [-] key to set the date value 7. Press the [SET] key to flash the temperature unit, press the [ALTI or and] key to switch between or 8. Press the [SET] key, the HPA air pressure unit flashes, press the [ALTI or and] key to switch to the HPA or inHg or mmHg air pressure unit The altitude displayed on the screen after power on is the sea level altitude of the current location. In the state of altitude display, press [SET] and [ALTITUDE or and] keys at the same time, you can press [and] or [-] to change and set the current altitude value.The method to reset the altitude value is to press and hold the [ALTI or and] button until 0M is displayed at the bottom of the screen, and then start to move, the relative altitude value of the movement will be displayed on the screen, and then press and hold the [ALTI or and] button to return to the actual altitude value.In barometer mode, pressHISTORYkey to view historical barometric pressure records. Whenever you enter this mode, the oldest recording will always be shown. Press [ALTI or and] or [-] key to display the history record forward or backward. Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.