Wireless microphone System 4 channel 4 bobypack 4 Lapel Mic 4 Headsets 3 year free warranty (521.5, 530.1, 536.8, 543.7) or (542.2, 544.4, 556.8, 560.8 )MHz Our store has 2 different frequency products?Frequency A is Green LED display ?This is Frequency B with Orange LED display. Buyers can use 2 different sets ( green & orange sets )at same time same place without interference. Features: 4 Channel 4 bobypack 4 Lapel Mic 4 Headsets Individual Volume Control on each Channel One 1/4" Mixed and four XLR" Individual Outputs Perfect operation status indicater 2 Telescoping Receiver Antennas Broad frequency response range, super low distortion Full metal design Use 2*1.5V battery Specifications: Overall System Number of Channels:4 channels Carrier frequency range:500MHz-580MHz Stability:±0.006% Normal deviation:±22kHz S/N ratio:<120dB T.H.D:<0.6% Frequency response:50Hz-15kHz Receiver Sensitivity:>80dB Audio output:Balanced and Unbalanced Power requirement:AC 16V,1000mA Dimensions:510×290×70mm Weight(weight):Approx.7.5bl Wireless Microphone Cartridge:Dynamic Antenna:Built-in RF output:<10mW Normal deviation:±22kHz Maximum deviation:±80kHz Comes With 4 x Lavalier Microphones 4 Lapel Mics 4 Headsets Base Transmitter US 110-240v Power Adapte