【Digital to Analog Audio Converter】 This DAC converter can convert optical, coaxial and Bluetooth transmitted digital audio signals into 3.5 mm audio signal output. Addresses an issue when connecting different audio interfaces to an analog amplifier..【Bluetooth 5.2 receiver with antenna】Bluetooth 5.2 version of lossless transmission technology and Bluetooth dedicated antenna, can achieve stable signal transmission. Support Bluetooth pairing to mobile devices (such as mobile phones, tablets). Support SBC, AAC decoder and signal distance up to 15 meters, using Bluetooth antenna..【Music Player with USB Flash Drive】It is also a digital music player with USB flash drive input that supports MP3, WAV, APE, FLAC and WMA lossless formats. You can always play music files stored on a USB flash drive and output to speakers via optical 3.5mm for better sound quality..【Widely used】Digital to analog audio converter is suitable for home theater, teaching, training structure, conference room, electrical appliance store and other places..【Promise volume adjustment】Professional volume control knob makes it very easy to adjust the output volume of AUX, choose coaxial/Toslink input or whether to mute and power on.