Sennheiser Set 810 Notice D'emploi page 32

BA 151 rechargeable battery
By using a spare accupack, you can use the stethoset receiver for more than
four hours of continuous operation. Always store the spare accupack in the
small charging compartment at the right of the transmitter. The right LED on
the transmitter lights up green to show charging is taking place. When
charging an battery in the small charging compartment, the charging time is
10-12 hours.
A battery has a service life of 1-2 years and should be replaced if the
operating time decreases.
Sennheiser batteries can be recycled. Please dispose of the battery as special
waste or return them to your specialist dealer. To protect the environment,
only dispose of totally exhausted accupacks which cannot be recharged.
L 151-2 charger
Spare batteries can be charged via the L 151-2 charger.
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