4-Channel Professional VHF Handheld Wireless Microphone System 4 Channel Receiver with 4 handheld Microphones 19" Rack Mountable / Range 120 feet (40 Meters) Individual volume controls on each Channel / 1/4" audio unbalanced output Available Frequencies ( Set 1: 186.20Mhz, 210.6Mhz, 192.6Mhz, 209.0Mhz ) and ( Set 2: 276.4Mhz, 202.2Mhz, 180.4Mhz, 206.0Mhz ) AA Battery Handheld / Battery Life: 12 Hours