Included: BLX4R single channel half-rack wireless receiver with rack mount kit; BLX1 bodypack transmitter; SM35 Headset Condenser Microphone; PS23 power supply. SM35 Headset cardioid condenser microphone for performance. BLX1 Bodypack Transmitter The BLX1 bodypack has a lightweight and durable design. Ergonomically designed to fit comfortably in hand, with adjustable gain control. For use with BLX Wireless systems. BLX4R Single Channel Half-Rack Receiver The BLX4R is a rugged, metal rack-mountable receiver with simple set-up and intuitive controls. One-touch QuickScan frequency selection quickly locates the best frequency, while removable antennas allow for quick antenna distribution. Rack mount kit included. Available in four frequency ranges: BLX H8 (518-542 MHz)BLX J10 (584-608 MHz)BLX K12 (614-638 MHz)BLX M15 (662-686 MHz)