Note On Rechargeable Cell - Citizen Eco-Drive b740 Instruction Manual

12. NOTE ON RECHARGEABLE CELL

The rechargeable cell used in this watch is a clean energy battery that
incorporates no toxic substance such as mercury inside. The rechargeable cell
has no need of periodical replacement because it is capable of repeated
charging and discharging.
However, power consumption may increase after using for an extended period
of time due to deterioration, and the power may run out earlier than expected.
To avoid this, we recommend that you have your watch inspected (Charge
basis) periodically.
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