SUUNTO AMBIT2 R User Guide - Manual (Page 79)

WARNING: People who have a pacemaker, defibrillator, or other
implanted electronic device use the hear rate belt at their own risk.
Before starting the initial use of the heart rate belt, we recommend
an exercise test under a doctor’s supervision. This ensures the safety
and reliability of the pacemaker and heart rate belt when being
used simultaneously. Exercise may include some risk, especially for
those who have been inactive. We strongly advise you to consult
your doctor prior to beginning a regular exercise program.
NOTE: Suunto Ambit2 cannot receive the heart rate belt signal
under water.
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