Fangrui Product Details Solution, Bluetooth Version 5.0 Lossless Playback, Double Decoding Mp3, Wma, Wav, Flac, Ape Lossless Format Music/read Usb Disk/read Tf Card/radio Fm/external Input Line In/infrared Remote Control/power Off Memory/power Supply Prev/vol- : To Select The Previous Song. Long To Lower The Volume Play/pause: Short To Switch Between Pause And Play; Long Is Usb/tf/fm/aux/bluetooth Sound Switch, In The Fm Radio Status, Automatically Search The Short Play Pause Key; Next/vol+ : Tap To Select Song. Long To Increase The Volume; Compatible With Mp3 / Wma/wav/flac/ape Three Buttons: Prev/play/next; 1, Prev (previous Song/volume Down) Key: Mp3 State, The Previous Short To The Previous Song, Long To Reduce The Volume; 2, Play/pause: Mp3 State Short To Play/pause; And Hold The Test Tone Switch Of Usb/tf Card /aux/ Bluetooth Mode. 3, Next (next Song/volume Increase) Key: In The Mp3 State, Short A Song, Long To Increase The Volume; This Model Has The Function Of Automatic Conversion Device. If No Device Is Available, Th