The Sennheiser EW IEM G4-A (article 509609) is a complete wireless in-ear monitoring system from the Evolution Wireless G4 series, used by performing musicians, worship teams and presenters who need a personal monitor mix on stage without floor wedges. The set combines the SR IEM G4 half-rack stereo transmitter in a full-metal housing with OLED display, the EK IEM G4 bodypack receiver and IE 4 in-ear headphones. This A-range version tunes across 516 - 558 MHz with up to 42 MHz bandwidth, 1680 selectable frequencies and up to 16 compatible channels, and syncs transmitter to receiver by infrared. RF output is up to 50 mW depending on local regulations, giving a range of up to about 100 m. The transmitter accepts two balanced XLR/6.3 mm jack combo inputs and has a BNC antenna output, while the bodypack delivers audio via a 6.3 mm stereo jack socket, with a frequency response of 25 Hz - 15 kHz and better than 90 dB signal-to-noise ratio. The receiver runs about 4 to 6 hours on two AA batteries, and the system works with Sennheiser's WSM software for frequency coordination. Check local frequency licensing before use.