The SENNHEISER's EW 100 G4-ME4 is a rackmount wireless microphone system that provides presenters, clergy, lecturers, and performers working in business and educational settings. A genuine diversity half-rack receiver is contained in a sturdy, full-metal chassis in the EW 100 G4-ME4. The receiver's auto-scan function looks for a clean, interference-free channel for your audio transmission across a wide 46 MHz UHF tuning range with 1840 selectable frequencies. The ME 4 cardioid lavalier microphone included with this device is optimised for speech intelligibility in noisy conditions. With a set 30mW RF power output and a transmission range of up to 330', the bodypack transmitter can run for up to 8 hours on two AA batteries. Up to 12 wireless microphones can be used in the same place at the same time, with the receivers linked together for quick multi-channel frequency setting.