... trolley speaker, with USB/SD/FM radio/Remote control/wireless microphone Technical parametersFrequency response: 80Hz-18KHzRated power: 50RMSSpeaker ... music format3. with remote control 4. With one Guitar input and one microphone input, one AUX input. ... promotion, outdoor activities, travel, meetings, singing, refining piano guitar,company meetings, outdoor performances, School indoor and outdoor large ...