Support protocols: A2DP, AVRCP, HFP, SPP HID. Receiving working current: 43MA. Transmitting working current: 60MA. Standby current:18MA. Built-in battery: polymer battery. Charging current: 300MA. Battery life: 8H. Bluetooth distance: 10M (open space). Charging method: Micro USB 5V/0.5A. Output connection method: 3.5MM stereo interface. Input connection method: 3.5MM stereo interface. Features: Support stereo codecs, HFP, HSP, A2DP, AVRCP, and SPP profiles. Noise reduction and echo cancellation. Multi-band equalizer configuration. Support packet loss concealment. Multi-point HFP and A2DP. Support voice prompts. Integrated lithium mode battery charger supports 300 mAh fast charging and over-discharge protection. Support audio equipment with audio input to achieve wireless audio reception and transmission. Support automatic search and connection of Bluetooth devices to achieve wireless audio transmission. Built-in AEC echo cancellation and ANC noise cancellation circuits, gorgeous stereo, purer sound quality. Built-in enhanced signal transmission circuit, faster and more stable connection without interruption. Compatible with dual lossless audio formats. Support AUX OUT, Earphone. Automatic memory connection function, simpler operation and more convenient connection. Package Included: 1set Bluetooth Audio Transmitter