Shure Instrument Wireless System, includes Beta 98H/C Mic, BLX1 Transmitter & BLX4 Receiver, K12: 614 - 638 MHz. The Wireless System combines professional-quality sound with simple setup and an intuitive interface for legendary audio performance right out of the box. Precision-built and available in a variety of configurations, it's the most accessible way to own the stage. It gives you world-class design and rock-solid build quality, along with easy setup and operation.