Product detailsP9 Wireless Bluetooth headset Supports Stereo Music Supports TF card Spot with microphone , transmission distance 10m , Battery Capacity 400mah , sensitivity ~ 3db , Speaker Diameter : 40mm , Playtime 10hrs , Standby time 12hrs , charge time 2hrs , Built – in – microphone YES , TF Card Support , Charging Port USB , Song Switching Support , Audio Interface support