SPECIFICATION   Mode A-688U Frequency Response VHF165~265KHz Max Output Power 110W Built in Features USB/SD/ Channels 1 Output Impedance 4ohm Speaker one full range 8'' Operating Voltage Built-in rechargeable battery Operating Temperature -10 ~45 Charge Time 6~8 hours Distance 35M Option Mic Transmitter or bodypack+headset mic or Lavalier mic Operating Time Continued using 6~7 hours in rich state Of rechargeable