RX & TX MODE: The Bluetooth adapter is a smart bluetooth transmitter and receiver, supporting both Bluetooth receiving and transmitting, namely RX and TX mode. RX mode turns your old wired headphones, CD player, speakers or car/truck into Bluetooth function enabled. TX mode equips your desktop, TV and TV BOX with Bluetooth so that these equipment are able to connect your Bluetooth earphones speakers. | BLUETOOTH 5.0 AUX ADAPTER：This Bluetooth transmitter receiver features advanced Bluetooth 5.0 technology, has an unrivalled performance with 2 times faster transmission speed, stronger connection stability and wider signal range.Up to 33ft/10m transmission range without any loss, allow you to enjoy HiFi stereo music without wire restriction. | MICROPHONE: The Bluetooth aux adapter has phone calls function,can be listened and answered easily and safely through the car’s stereo and the car audio adapter’s microphone, no need to dangerously take cellphone out from pocket or stand. Long press the phone/play key to activate the voice assistant of cellphone and talk to this bluetooth audio adapter’s mic to let your cellphone change a song, make a call, send a message etc. | LOW DELAY PURE STEREO: The bluetooth transmitter receiver uses Aptx and DSP codec technology contributes to a richer and deeper stereo experience with low latency and high fidelity. Enjoy CD-like audio quality all the time. | ALWAYS ON: EWIN 3-1 wireless bluetooth audio adapter can still work while charging. Built in batteries for up to 7-8 hours use and automatic shutdown after no connection for 5 minutes.