Inappropriate use
Inappropriate use includes if you use the headphones differently than described in the instructions, or do not maintain operating conditions.
Safety instructions for battery and rechargeable battery use
Batteries/rechargeable batteries can leak with abuse or improper use. In extreme cases, there is the risk of explosion or fire. Sennheiser therefore assumes no liability in cases of abuse or improper use.
Do not store in reach of 
children.
Do not heat or throw into fire.
Do not short circuit.
Do not solder.
Do not disassemble or 
deform.
Do not mix batteries and 
rechargeable batteries 
without packaging.
Do not mix empty and fully charged batteries/ rechargeable batteries.
Do not charge disposable batteries.
Immediately remove empty batteries/rechargeable batteries from the device.
Observe polarity.
Switch off (rechargeable) battery operated devices after use.
Remove batteries/rechargeable batteries from the device if will not be used for an extended period.
Use only appropriate Sennheiser chargers for rechargeable batteries.
Recharge rechargeable batteries after longer periods of disuse before using.
Only charge rechargeable batteries 
at ambient temperatures between 10 °C and 40 °C.
Only dispose of used batteries/ 
rechargeable batteries at collection 
sites or return them to your dealer.
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