Small but mighty: the clip-on microphone in this professional set is nearly invisible. The included cardioid pattern microphone has both great resistance to feedback and clear voice reproduction. The true diversity receiver means you get the highest degree of signal reliability at all times. Sync up the bodypack with the receiver with a single touch of a button. Especially convenient: you can connect an external mute button (option) to the additional 2.5 mm jack socket on the bodypack transmitter.As the wireless mic field becomes more crowded and bandwidth becomes more limited, Sennheiser has taken on the task of staying ahead of the curve. When you buy Sennheiser, you're not just buying quality, you're also buying security! Security against obsolecence as well as performance security . No drop outs, no interfence, no hum and no RF! Just crystal clear audio without the tangled mess!