MS-B4

Bluetooth Version:V5.3
chipset:JL6956A
Support a2dp/avcto/avdtp/avrcp/hfp/
spp/smp/att/gap/gatt/rfcomm/sdp/
12cap profile
Bluetooth Distance : 15meters
Impedence:32ohm
Frequency Range: 20-20khz 
Sensitivity: 98dB±3dB/mW
Earphone Battery:400mAh
Driver Size:40mm
Charging Time：2hours
Playtime(100%volume ): 20hours(LED off)/8hours(LED on)