Quartz Lock For Drift-free Operation Four Microphones Included Audio Mute Circuitry For Quiet Operation Af Signal Led Segment Meter On Each Channel Individual Channel Volume Controls Individual 1/4'' Unbalanced Outputs Xlr Balanced & 1/4'' Unbalanced Mixed Output Operation Range Up To 240 Ft Battery Life Approx. 12 Hours Frequency Range: 210 Mhz - 280 Mhz 110v - 220v Selectable Includes 4 Microphones, Rack Hardware, Batteries & 1/4'' Audio Cables