Shure BLX24/SM58 Handheld Wireless System with SM58 Vocal Microphone, J10 Included: BLX4 wireless receiver; BLX2/SM58 handheld transmitter with integrated SM58=- cardioid dynamic microphone capsule; microphone clip; padded zipper case Power and battery status LED Adjustable gain control Quick & easy frequency matching 2 AA batteries (included) provide up to 14 hours of continuous use 300 feet (91 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)