Huawei ETS8121 User Manual page 13

On a stormy day with thunder, do not use your device when it is being charged,
to prevent any danger caused by lightning.
When you are on a call, do not touch the antenna. Touching the antenna
affects the call quality and results in increase in power consumption. As a
result, the talk time and the standby time are reduced.
While using the device, observe the local laws and regulations, and respect
others' privacy and legal rights.
Keep the ambient temperature between -10° C and 45° C while the device is
being charged. Keep the ambient temperature between -10° C to 55° C for
using the device powered by a battery.
Prevention of Hearing Damage
Using a headset at high volume can damage your
hearing. To reduce the risk of damage to hearing, lower the headset volume to a
safe and comfortable level.
Safety of Children
Comply with all precautions with regard to children's safety. Letting the child play
with your device or its accessories, which may include parts that can be detached
from the device, may be dangerous, as it may present a choking hazard. Ensure
that small children are kept away from the device and accessories.
Accessories
Use the accessories delivered only by the manufacturer. Using accessories of
other manufacturers or vendors with this device model may invalidate any
approval or warranty applicable to the device, result in the non-operation of the
device, and cause danger.
Battery and Charger
Unplug the charger from the electrical plug and the device when not in use.
The battery can be charged and discharged hundreds of times before it
eventually wears out. When the standby time and the talk time are shorter than
the normal time, replace the battery.
Use the AC power supply defined in the specifications of the charger. An
improper power voltage may cause a fire or a malfunction of the charger.
Do not connect two poles of the battery with conductors, such as metal
materials, keys, or jewelries. Otherwise, the battery may be short-circuited and
may cause injuries and burns on your body.
Do not disassemble the battery or solder the battery poles. Otherwise, it may
lead to electrolyte leakage, overheating, fire, or explosion.
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