Sennheiser Conversation ClearPlus True Wireless ANC Speech Enhancer - Manual (Page 13)

Using the earbuds
Conversation Clear Plus | 13
Using the earbuds
Information on the rechargeable battery,
the charging process and the first use
The earbuds and the charging case each have a built-in rechargeable
battery. The charging case allows you to store the earbuds safely at
all times while on the go, and they are being charged at the same
time.
Upon delivery, the rechargeable batteries of the earbuds and the
charging case are in sleep mode. Connect the charging case to a
USB power source to exit sleep mode.
A complete charging cycle of the charging case and the earbuds
takes about 5 hours. The quick charge function gives you approx.
1 hour of playback time after 15 minutes of charging. The charging
time may vary depending on the power source used and the ambient
temperature.
We recommend charging the earbuds and the charging case for a
complete charging cycle without interruption before using for the
first time.
We recommend using the supplied USB cable and a compatible
standard USB power supply for charging the earbuds.
When a USB cable connected to a power source is also connected to
the charging case, the rechargeable battery of the charging case is
being charged. When the earbuds are inserted into the charging
case, their rechargeable batteries are being charged at the same
time. The LED display of the charging case displays the charge
status (> 8).
When the charge status of the earbuds' rechargeable batteries drops
to a critical level, a sound sequence prompts you to recharge the ear-
buds.
The charge status of the rechargeable battery of the charging case
is displayed by the LED display on the charging case (> 8).
At the end of its operational lifetime, this product with its built-in
rechargeable battery must be disposed of separately from normal
household waste. You can find more information here: > 41.