We are manufacturer, professional power amplifier. 1, 60W 2, USB Playing it, FM Radio station. SD card. 3, Has passed CCC,CE. ModelRated powerOutput modelInput sensitivityS/n ratioFred ResponsePower workDimensionsC60U60W70V100V4-16Ω500mv>85dB80Hz15KHz+_3dBAC220V+_10%/50Hz66*350*250We are manufacturer, professional power amplifier.1. 60W2. USB Playing it. Radio station. SD card.3. Short circuit. ...