portable wireless amplifierHigh quality Lithium battery portable voice amplifier ,show a clear voice, strong volume, the ... :200 to 270mhz; 80db 2.transmitter: 200to 270mhz; >80db ;9v battery ;30ma 3. main unit:200v ;100hz to16khz; inputs: wire mic ... inches*1, 3inches*1 e.220v ac,12v 4.5ah* rechargeable battery, 30m, 220*270*145mmPackaging including:Main unit: 1 piece Waistband ...