AKG PW45 Sport Set B1 - Perception UHF wireless system with pocket transmitter and C544L headset microphone, 5 switchable frequencies B1 range (748,100 - 751,900MHz), 9.5" diversity receiver with internal antennas, adjustable output volume, XLR out, transmitter requires 1x AA or rechargeable battery, low battery display, on/off/mute switch on transmitter. Includes power supply, C544L and 1x AA battery. Please note: Due to every country having different regulations, you may need to contact your local licensing authorities before using a wireless system.