Bluetooth 5.3 Audio Adapter: Upgrade your non-Bluetooth devices to Bluetooth-enabled ones, including vintage stereos, speakers, TVs, and car stereos with this Bluetooth adapter. Enjoy better stability and faster connections with the latest Bluetooth 5.3 chip. 2-In-1 Bluetooth Receiver & Transmitter: In transmitter mode(Tx), the Bluetooth adapter is plugged into non-Bluetooth audio sources such as TV/airplane entertainment and transmits audio to Bluetooth headphones/speakers. In receiver mode(Rx), it receives audio from your phone/tablet via Bluetooth and plays on the car stereo, wired headphones/speakers. Support RCA & AUX 3.5mm Audio: Enjoy a wider range of audio sources with this Bluetooth transmitter & receiver. It supports 3.5mm(AUX) and RCA(L/R) audio, TF Card & USB Disk Play(in receiver mode), and is plug and play. User-Friendly Knob: Allows you to control everything: Short press it to pause/play music or answer/hang up a call, and rotate it to control volume.