... DC 12V 3. Built-in battery 12V , 7AH Speaker unit: 12 inch +1.5inch Wireless system: one wireless microphone Cable system ... adjusttrebletoadjustthemicrophone volumeOK reverberationBrand name: konstar or OEM, Model: KS-A12(12'') Scope of applicationGymnastics, dancing, teaching, product promotion, outdoor activities, ... groups, the elders'fitness outdoor. Brazil hot model trolley speaker 12'' 15''