The ew IEM G4-Twin Wireless Monitor System from Sennheiser is part of the evolution family of wireless monitoring systems and includes an SR IEM G4 transmitter, two EK IEM G4 stereo receivers, two pair of IE 4 earphones, a rod antenna, GA 3 rackmount kit, and four AA batteries. This kit can be used as a rugged, all-in-one, two-person wireless in-ear monitoring system for live stage, theater, and house-of-worship applications. The system provides up to 1680 frequencies tunable in 25 kHz steps to deliver clear, audio without interference and dropouts. Additional transmitters and receivers can be added for up to 16 wireless IEM channels.