Green Lion Echo Max Headphone

Charging: USB-C / USB-A cable included
Autonomy: 50 hours at 50% of the max volume in Bluetooth mode
Integrated battery: Lithium-ion polymer 3.7V 500 mAh
Headset sensitivity : 102 dB + 3 dB
Frequency range: 20Hz – 20kHz
Signal/noise ratio : 90 dB
Maximum range: 10m
Impedance: 32Ω
Bluetooth: V 5.3