Bluetooth 4.2 Fresh ion (AVRCP 1.6 and A2DP 1.3)Compared with 4.1 Bluetooth Transmitter / Receiver, the Bluetooth 4.2 aux adapter features aptX low latency technology and AAC / SBC codes, freely enjoying clear HiFi stereo sound without sync delay. NOTE: The aptX low latency is only supported in TX mode.Dual Modes Reception & TransmittingRx (received):Use the receiving function to stream music from smartphones, tablets to any 3.5mm-In or 2RCA-In device.Tx (Send):It supports to connect an audio output device such as PC, TV and Mp3 to Bluetooth capable device such as Bluetooth headphones, earbuds and speakers.Two-point Connection Function Enabled:Pairing two Bluetooth headphones simultaneously TV, Laptop, etc. connect two smartphones to the non-Bluetooth speaker at the same time. Please be kindly noted that the two devices must be within 5 meters.Built-in BatteryBuilt-in battery for the Bluetooth transmitter receiver to work extend time.