About The Rechargeable Cell - Citizen Eco-Drive 200 Meter BM6400-00E User Manual

E. ABOUT THE RECHARGEABLE CELL
Unlike ordinary watches, the special rechargeable cell used in your watch
does not need regular replacement. This is a clean energy cell that will last
the life of the watch.
CAUTION:
The rechargeable cell should last the life of the watch. Never allow anyone other
than an Authorized Service Center to replace this cell. The movement is designed
to operate with only the original rechargeable cell. If an alternate cell is installed,
such as a conventional battery, the battery may become overcharged resulting
in damage to the movement and/or bursting of the cell, which could cause injury
to the user.
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