Silvercrest STSK 2 C3 Operation And Safety Notes page 72

Wireless charging power 2 .5 W
Wireless charging
distance to the Qi charger ≤ 5 mm
Frequency band
Transmitted maximum
radio frequency power
(H-field)
Rechargeable battery
Charging capacity
Charging time of the
charging/storage boxes'
built-in battery
72 GB/IE
112 .18-
146 .15 kHz
–13 .9 dBµA/m at
10 m distance
Li-ion polymer,
3 .7 V, 550 mAh,
2 .0 Wh
up to 5 complete
charge cycles for
fully discharged
headphones
approx . 3 hours
(complete charging
cycle)