Feature 1 Professional Design: Bluetooth receive or transmit mode and optical coaxial digital to analog conversion. u disk AUX sound input, multi device expansion interface, to meet different needs. 2 Plug and Play: Connect old speakers or amplifiers AUX RCA interface, solve the problem of speakers without Bluetooth, can not use Bluetooth playback, support U disk playback, driverfree, plug and play. 3 HiFi Lossless Sound: Bluetooth receiver transmitter with HIFI shock lossless level sound quality, clear and noiseless, enjoy good music, natural good mood, support format MP3 APE FLAC WAV WMA. 4 Bluetooth 5.1: Bluetooth aux adapter uses Bluetooth 5.1 chip, transmission signal stability, low latency and high restoration of sound signals in the wireless transmission, hifi sound data restoration, enjoy the sound quality of wired connection in the wireless connection. 5 Long Range: Bluetooth transmitting and receiving without pressure, 30M unobstructed stable transmission, music without delay, strong signal, so that the room connection without dead ends.Item Type: Bluetooth Receiver TransmitterMaterial: Aluminum AlloyRemote Control Battery Type: Built In 160mAh CR2025 Button Cell (Included)Bluetooth Version: Barrier Free 30m/98.4ftInterface Type: Optical, Coaxial, Aux, RCA, USB InterfaceBluetooth Protocol Support: A2DP and AVRCPMusic Format: MP3 APE FLAC WAV WMA Package List1 x Receiving Transmitter1 x Fiber Optic Cable1 x Sound Line1 x Power Supply Line1 x Remote Control1 x Instruction Manual