SUUNTO AMBIT3 PEAK - Manual (Page 16)

CAUTION: Keep the area around the sensor free of dirt and
sand. Never insert any objects into the sensor openings.
If your outdoor activity requires accurate sea level air pressure or
altitude, you need to calibrate your Suunto Ambit3 Peak by
entering either your current altitude or the current sea level air
pressure.
TIP: Absolute air pressure and known altitude reference = sea
level air pressure. Absolute air pressure and known sea level air
pressure = altitude.
The altitude of your location can be found from most topographic
maps or Google Earth. A sea level air pressure reference for your
location can be found using the websites of national weather
services.
If Suunto FusedAlti
TM is activated, the altitude reading will be
corrected automatically using FusedAlti together with altitude and
sea level pressure calibration. For more information, see
3.13 FusedAlti .
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