This wireless package is designed for presenters who want the microphone to "disappear" on stage. The Shure MX153 is a beige-colored earset with a slender shaft and a tiny mic element. It is ideal for musical theater, plays, teleconferencing, church audio and business presentations. The BLX14R/MX53 system is additionally equipped with the BLX bodypack transmitter and the BLX4R rackmount wireless receiver. The BLX series bodypack transmitter works with lavalier and headset microphones, and also works for guitar with the appropriate cable connector. The beltpack features an On/Off hard toggle switch, preferring to eliminate the multi-function push button that is used on some wireless transmitters. Many users found the multi-function single button to be inconvenient and unreliable. The BLX4R reciever includes all of the hardware you need to install this system into a road rack. It is a true diversity two-antenna system with channel scan and XLR and 1/4" outputs. FEATURES Omnidirectional polar pattern CommShield Technology guards against interference Cable design reduces handling noise while providing superior flexibility Rackmount receiver Warranty years.