POLAR S610i - Manual (Page 74)

Batteries
Transmitter
The estimated average battery life of the transmitter is 2500 hours of
use. Contact your authorized Polar service center for a replacement
transmitter. Polar recycles used transmitters. See your Customer Care
Charter for detailed instructions.
Wrist Receiver
The estimated average battery life of the wrist receiver is 2 years in
normal use (2h/ day, 7 days a week). Please note that excessive use of the
backlight and the alarm signals will drain the battery more rapidly. Do
not open the wrist receiver yourself. To ensure the water resistance
properties and the use of qualified components, the wrist receiver
battery should be replaced by an authorized Polar Service Center only.
At the same time a full periodic check of the Polar heart rate monitor
will be done.
Service
Should your Polar heart rate monitor need service, see the Customer Care
Charter to contact an authorized Polar Service Center.
Water resistance cannot be guaranteed after unauthorized service.
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