Mrice M880 Wireless Foldable Bluetooth Headphones For Music Stream&Handsfree Calling With Build-In Microphone,Line-In Port

Specification:

Bluetooth Version: V4.0
Product: Wireless Bluetooth Headset
Product Size: Φ30mm (Driver)
Packing Size: 265*200*65mm
Material: ABS+PC
Weight: N/W 137g G/W 550g
Colour: Black, Black+Red, White+Silver
Rated Power: 10mW (Max Power 30mW)
Rated Impedance: 32Ω±10%
Sensitivity: 105±3dB (at 1kHz)
Distortion Degree: <1% 94dB (20μpa) 
Channel Balance: <2dB (at 1kHz)
Frequency Response: 20Hz~20kHz
Transmission Standdard: CLASS 2 (≤10m)
Standby Time: >150 hrs (Battery saturation)
Working Time: >6 hrs (Volume 50%)
Charging Time: 2~3 hrs
Charging Voltage: USB 5V (DC 5V 300mA socket)
Built-in Battery: Polymer lithium ion 3.7V 190mA
Channels: 79 channels of 1Mhz BW