A04I Electronic Altimeter Carabiner Altimeter Handheld Thermometer Outdoor Fishing Weather Forecast Mode Meter Outdoor Gadget Barometer: The current barometric pressure be displayed on the screen immediately after power on. Press the [ALTI/+] button to switch between barometer and altimeter._x000D_ Altimeter: The altitude value displayed on the screen after power on is the sea level altitude of the current location. In the altitude display state, press the [SET] and [ALTITUDE/+] keys simultaneously, you can press [+] or [-] to change the current altitude value._x000D_ Relative altimeter: The use of the relative altimeter is to clear the height value measured at this time, and use the position at this time as the 0M height point, and the height value rising or falling from the 0 height point is the relative height value._x000D_ The method for resetting the altitude value is to press and hold the [ALTI/+] button until 0M is displayed at the bottom of the screen, and then start to move, and the relative altitude value of the move be displayed on the screen. Press and hold the [ALTI/+] button again to switch back To the actual height value._x000D_ Weather forecast: It can predict the weather conditions in 12 to 24 hours when it is turned on, and the effective range is 30-50KM. 1. Long press the [SET] button for 2 seconds, 24Hr flashes, press the [ALTI/+] button to switch between 24Hr or 12Hr_x000D_ 2. Press the [SET] button to enter the time setting, at this time the hour digits flash, press [ALTI/+] or [-] to set the hour value_x000D_ 3. Press the [SET] button to flash the minutes, press [ALTI/+] or [-] to set the minutes_x000D_ 4. Press the [SET] button to flash the calendar year number, press the [ALTI/+] or [-] button to set the year value_x000D_ 5. Press [SET] button to flash the calendar month number, press [ALTI/+] or [-] button to set the month value_x000D_ 6. Press the [SET] button to flash the calendar date number, press the [ALTI/+] or [-] button to set the date value_x000D_ 7. Press the [SET] button to flash the temperature unit Celsius, press the [ALTI/+] button to switch between Celsius or Fahrenheit_x000D_ 8. Press the [SET] button and the air pressure unit flashes, press the [ALTI/+] button to switch to the air pressure unit /inHg/mmHg_x000D_ 9. Press the [SET] button to flash the height unit M, press the [ALTI/+] button to switch between the height unit M or FEET_x000D_ 10. After the setting is completed, press [HISTORY] to exit the setting state, or automatically exit the setting without doing any operation within 10 seconds_x000D_ colour:Black grey_x000D_ Material:ABS_x000D_ size:9 x 5 x 2cm Package Contents:_x000D_ 1 x altimeter barometer_x000D_ 1 x English manual_x000D_ 1 x CR2032 button battery (not included) Only the above package content, other products are not included._x000D_ Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_