Citizen P991 Guide De Démarrage Rapide page 4

3 BLOOD OXYGEN TRACKING
Wear your watch slightly higher up your arm and avoid pressing your watch against your wrist
bone. Make sure your watch fits comfortably on your wrist. Wearing your watch too tight
constricts the blood circulation while wearing it too loose may let other light in, which affects
the measurement. Place your hand on a flat surface with your fingers resting open. The back of
your watch should be in contact with your skin. Stay still and avoid interacting with the watch
during the measurement.
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