This adapter Bluetooth 5.1 version, the signal is stable without delay, and the transmission distance is 20 meters without obstacles. Connect an external antenna to increase the signal receiving distance. Bluetooth receiver adapter, connect old speakers/amplifiers, turn wired devices into Bluetooth projects, and play music anytime, anywhere. Digital-to-analog audio converter, 3.5mm auxiliary coaxial fiber input, RL/3.5mm output, compatible with TV/PC/projector/amplifier/TV Box. Support U disk playback. Support bass mode and volume control. Support WAV/FLAC/MP3/APE/MAV music format. Product name: Bluetooth receiver and DAC audio converter Bluetooth version: 5.1 Mode: Coaxial/Optical/U Disk/Bluetooth Power input: 5V Colour: black Material: aluminum alloy Package Contents: 1 * Bluetooth 5.1 digital analog audio converter (110x25x85mm/4.3x0.98x3.34inch) 1 * Coaxial cable (80cm/31.5inch) 1 * Fiber optic cable (80cm/31.5inch) 1 * 3.5mm AUX audio cable (80cm/31.5inch) 1 * USB-C power supply line (80cm/31.5inch) 1 * Remote control (without 2 AAA battery) 1 * English manual Only the above package content, other products are not included. Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.