USB, TF ,FM Output Power : 20wFrequency Rosponse : 100Hz-10KHz±3dbSensitivity : ≥75dBType of Battery : lithium-ion 7.4V 1800mAHPower Adaptor : DC:12V / 500MAMusic Tone : MP3Audio Input : USB,TF,FM,Wired MicUSB,TF up to 2GDimwnsions : 125*45*87mmStandard Configuration : amplifier(inch. waistband),headset mic,recharger,remote control WAIST BAND USB MP3 AMPLIFIER (K7800)