LG TONE Free Owner's Manual page 7

Risk of fire or explosion if the battery is replaced by an incorrect type.
Do not store or transport at pressures lower than 11.6 kPa (0.116 bar)
and at above 15,000 m (9.32 miles) altitude.
Replacement of a battery with an incorrect type that can defeat a
safeguard (for example, in the case of some lithium battery types).
Disposal of a battery into fire or a hot oven, or mechanically crushing or
cutting of a battery, that can result in an explosion.
Leaving a battery in an extremely high temperature surrounding
environment that can result in an explosion or the leakage of flammable
liquid or gas.
A battery subjected to extremely low air pressure that may result in an
explosion or the leakage of flammable liquid or gas.
Do not carelessly throw away old batteries. It can cause an explosion or fire.
The disposal method may vary by country and region. Dispose of it in an
appropriate manner.
NOTE
If the product is exposed to excessive sweat, clean the product.
Keep the earbuds clean.
Wearing earbuds for a long time may cause pain, and if humidity inside
ears continues for a long time, it may cause skin trouble.
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