Quantity: 1Parameter setting1. Press and hold the [SET] button for 2 seconds, 24Hr flashes, press the [ALTI/+] button to switch between 24Hr and 12Hr2. Press the [SET] button to enter the time setting, the hour digit flashes, press [ALTI/+] or [-] to set the hour value;3. Press the [SET] button to flash the minute digit, press [ALTI/+] or [-] to set the minute value;4. Press the [SET] button to flash the year digit of the calendar, press [ALTI/+] or [-] to set the year value;5. Press the [SET] button to flash the month digit of the calendar, press [ALTI/+] or [-] to set the month value;6. Press the [SET] button to flash the date digit of the calendar, press [ALTI/+] or [-] to set the date value;7. Press [SET] button, the temperature unit flashes, press [ALTI/+] button to switch to temperature unit or ;8. Press [SET] button, the pressure unit HPA flashes, press [ALTI/+] button to switch to pressure unit HPA/inHg/mmHg;9. Press [SET] button, the altitude unit M flashes, press [ALTI/+] button to switch to altitude unit M or FEET;10. After setting, press [HISTORY] to exit the setting state, or if no operation is performed within 10 seconds, the setting will be automatically exited;11. Press [SET] button to switch the display mode of time and calendar.Functional introduction1. Electronic altimeter (measuring range: -700~9000 meters/-2300~29500 feet)2. Electronic barometer (300-1100mbar)3. Weather forecast4. Historical altitude and pressure records (256 records can be scrolled)5. Electronic thermometer (Celsius or Fahrenheit can be displayed)6. Clock (12/24 hour system, display hours, minutes, seconds)7. Calendar (display year, month, day)8. Backlight (white): Press any key in any state to turn on the backlight. Press any key when the backlight is on to extend the backlight time by 5 seconds. If no key is pressed, the backlight will automatically turn off after working for 5 seconds.