Offer 100 selectable frequencies on each channel mic A 536 57 561 32 mic B 562 37 587 12 We update each microphone frequency from 40 to 100 which can more effectively avoid interference Two ways to change the frequency Automatically scan the best way to find the best frequency for your system for multiple system setup you could manually set the channel number Manual frequency pairing can easily synchronize Battery Life 14 17 Hours Working Range in wide open area 180 240 Ft 60 80m line of sight Extra Two XLR individual outputs and one 1 4 Mixed output Better to have a power amplifier if you want to get a good effect Metal microphone kit unidirectional Cardioid Vocal Sound quality is loud and clear ideal for church small DJ KJ stage birthday wedding or family party conference classrooms small karaoke night etc What you get Receiver 2 handheld microphones power adapter 1 4 audio cable 2 Antenna