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.