Usb: Connect To U Disk (maximum Support 32gb) Tf: Connect To Tf Memory Card (maximum Support 32gb) Aux: Audio Input Interface Vol-: Short Press Is The Last Song; Long Press Is The Volume Reduction. Play/pause: Short Press Is The Switch Between Pause And Playback; Long Press Is The Radio Fm Automatic Station. Vol+: Short Press Is To Choose The Next Song; Long Press Is To Increase The Volume. Mode: Switchover Of Usb/tf/fm/line In/bluetooth Voice Main Control Ic: Ac5322b Bluetooth Ic: Ac5322b Bluetooth Version Is Version 5.0 Music Format: Mp3/wma/wav/flac/ape Lossless Format Music Power: 2 * 3w, Connected To Two 3w Speakers Radio Fm Frequency: 87.5-107.5 Mhz Introduction Of Support Functions: Support Mp3/usb/tf/line In/fm/bluetooth/remote Control/dc 5v About Structure: Panel Size: 107 * 25 Mm, Panel Corner And Screw Hole Position, Then Cover Surface, The Depth Of The Board Is 32 Mm Description Of Recording Function 1. Press The Mode Button For A Long Time To Start Recording, And Then Press The Mode Button F