Product Features: Bluetooth version :Bluetooth V5.2 Support Protocol RX: A2DP AVRCP TX: A2DP Operating Frenquency :2.402GHz - 2.480GHz Signal-to-noise ratio :99.3dB Distortion :0.1% Support Dual stream(TX mode) :Connect two Bluetooth devices at the same time Support Multipoint (RX mode) :Connect two Mobile phones at the same time Codec mode CODEC TX: aptX Adaptive/aptX HD/aptX LL/aptX/SBC RX: aptX Adaptive/aptX HD/aptX/AAC/SBC Operating current :22MA Built-in battery :250MAH Charging current :200MA Charging time :2 hours Working time:RX:About 15h TX:About 13h Bluetooth distance :12M(open place) Charging method :USB TYPE-C 5V/0.5A Input/output connection :3.5MM audio interface