Shure BLX Wireless Systems combine 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. System Includes: BLX1 with up to 14 hours of continuous use with 2 AA batteries. 300 ft (100 m) transmission radius. BLX4R Rack-mountable receiver with removable antennas for quick distribution. SM35 Headset Condenser Microphone for use with Shure Bodypack Wireless Systems Features Frequency Range: 614MHz-638MHz Quick and easy receiver frequency matching TQG connection for use with Shure lavalier, headset, earset and instrument microphones and guitar cables Easily accessible On / Off switch The BLX4R rack-mountable receiver featuring rugged metal construction, the BLX4R offers simple setup and intuitive controls. One-touch QuickScan frequency selection quickly locates the best open frequency in case of interference. Removable antennas allow for quick antenna distribution. Rack mount kit included. XLR and ¼ inch output connectors Microprocessor-controlled internal antenna diversity Two-color audio status indicator LED - Green: Normal audio levels, Red: Excessive audio levels (overload / clipping) Adjustable output level LCD display with detailed RF and audio metering The NEW SM35 Headset Condenser Microphone for use with Shure bodypack Wireless Sytems. Wearable wireframe headset fits securely and comfortably for active performers and multi-instrumentalists Tight, unidirectional (cardioid) condenser pickup pattern rejects signal bleed and feedback for use on loud stages and behind floor monitors Flexible gooseneck design allows for optimized placement to further improve source isolation Lightweight and low-profile form enables comfortable, long-wearing use TA4F connector compatible with any Shure wireless bodypack system Included in a wide variety of Shure wireless systems, renowned for their ease of use and reliable performance Locking snap-fit windscreens tame plosives, breath and wind noise for clean and intelligible sound Tailored frequency response refined for clear, crisp vocal reproduction Legendary Shure precision engineering for durability and performance