... audio board) Function and features:pcb board for MP3/SD/USB, fm radio and digital screen display, with power on/off switch ... around 5 R&D StaffProduct Line: mini Card& USB reader speaker, portable FM radio speaker, mobile speaker, active speaker, tower speaker, ... stage speaker, ect.We can add USB/SD function and FM radio on multimedia speaker, mini speaker, active speakerRemarks: 1 ...