Connects an old speaker or amplifier audio interface to add Bluetooth playback to equipment that lacks Bluetooth. USB disk playback plugandplay Supports USB drives for music playback No driver required Bluetooth 5.3 upgrade Equipped with a performance Bluetooth 5.3 chip Lowloss data transmission and quick response Improved antiinterference for a more stable connection and reduced delay Multiple interfaces to fit different devices AUX input RCA red and white connectors Digital optical output USB disk input Designed to meet the needs of different devices and audio interfaces Use scenarios Home stereo upgrade: add Bluetooth streaming from a phone, tablet, or computer to an older speaker or amplifier that has no Bluetooth TV or computer connection: use AUX or optical output to improve wireless streaming quality to your existing audio system USB drive playback: play music directly from a USB drive through the connected speaker or amplifier without additional software This product maintains a professional, reliable performance while offering flexible compatibility across various devices and audio interfaces.