The AmpliVox SW664 Mobile Horn Array PA System is a 50-watt, totally wireless, highly intelligible, lightweight vertical loudspeaker system for general PA applications in areas that are not equipped with a PA system. The unique, horizontal mount, 4-horn, line array configuration maximizes sound dispersion over broad areas, producing consistent tonal balance with less volume drop-off over longer distances. The four horns broadcast highly intelligible voice announcements and reinforces sound to make it louder to people over large wide areas. Perfect for large outdoor venues such as ball fields, parks, open air arenas, and street fairs. The system can also be used indoors in loud environments such as manufacturing facilities. During emergencies, the quick to set-up battery powered design allows you to broadcast emergency information even during power outages.