2.4G USB wireless microphone 1.it convenient ... stage,etc 3.30W 2.4G USB wireless microphoneThis product is digital portable amplifier with ... lectures, dance,tour guides,Conferencing,Picnics,Trad show promotions,Coaching, gymnastics demonstrations, outdoor activities, hiking guide, street selling ... square provisional assembly, speech activities, the exhibition guide, such as shopping malls to promote the ...