Lenovo X9

Brand Name: Lenovo
Model Number: X9
BT Version: 5.0
Transmitting Distance: 10m/33ft
Drive Diameter: 13mm
Frequency Range: 20-20KHz
Sensitivity: 119±3dB
Impedance: 32Ω
Charging Case Battery Capacity: 3.7V 300mAh
Earbuds Battery Capacity (Each): 3.7V 30mAh
Music Play Time: about 4 hours (depends on music volume)
Charging Time: about 1.5 hours