SPECIFICATION   Mode A-221 Frequency Response VHF165~265KHz Max Output Power 50W Built in Features USB/SD/FM/LED Display Channels 1 Output Impedance 4ohm Speaker one full range 6.5'' 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