1.Power switch LED display,with USB port for charge 2.3-bit sound Mode transfer switch 3.High/low potential volume contro Total harmonic distortion:<0.1%l,S/N:90dBFrequency Response:20~20KHz l,distortion:<0.02(1KHz) Output Power:RMS 75W X 2CH (AT 12V DC INPUT)Supply voltage:9-15V DC1.High quality RCA input/output socket mini car amplifier,car audio , auto amplifier