Shure BLX1-J11 Wireless Bodypack Transmitter (J11: 596 to 616 MHz)Key Features For BLX Wireless Systems Use with Lav Headset Mic or Instrument TA4M Connector On Off Power Button Adjustable Gain Control 14 Hour AA Batteries The Shure BLX1 is a bodypack wireless transmitter compatible with BLX Series receivers. With a lightweight, ergonomic design, it is comfortable for performers and presenters to wear, while providing up to 14 hours of continuous use with the two included AA batteries, at a range up to 300'. Group