Description Specification: Model P9 wireless headphones Bluetooth version 5.0 Transmission distance  10m Battery capacity 400mAh Frequent response 20Hz-20KHz Sensitivity  105±3db Speaker diameter 40mm Call playback time  7-10 hours Standby time 120h Charging time  12h Usage mode Bluetooth T/F card mp3 mode Charging voltage  5V- 1A Support Song switching, Answering the Call/ Hang up the Call, Audio I/O interface