1.CE,ROHS,FCC,CB,ISO 2.Rechargeable battery 3.MP3 input 4.Suit for teacher, tour guide ,promo action ,army 5.MOQ 100pc A great help at home, office, factory, hospital, school, nursing home, church, retreat, camp, meeting, restaurant, party, ballgame, any place or event - one to one conversation or group activity - and in a car, bus, plane or train to get above engine and road noises.Function :1. ...