Shure BLX14/CVL Lavalier Wireless System with CVL Lavalier Microphone, H10 Includes BLX4 wireless receiver, BLX1 body pack transmitter, CVL Lavalier microphone, power supply, Lavalier clip, windscreens, and user guide. Power and battery status LED Adjustable gain control Quick & easy frequency matching 300 feet (91 m) operating range (line of sight) Quick and easy receiver frequency matching, easily accessible On / Off switch TQG connection for use with Shure lavalier, headset, earset and instrument mics and guitar cables Up to 14 hours of continuous use with 2 AA batteries (included), plus power and battery status LED 300 ft (100 m) operating range (line of sight) Up to 12 compatible systems per frequency band (region dependent), One-touch QuickScan frequency selection quickly locates the best frequency, and Microprocessor-controlled internal antenna diversity. XLR and &#034; output connectors. Two-color audio status indicator LED (Green:Normal audio levels / Red:Excessive audio levels)