1.CE,ROHS,ISO,FCC 2.Rechargeable speaker 3.USB/SD/MMC input,music reverb 4.MP3 input 5.fm Radio This mini speaker is widely used at home, office , school , church , factory , hospital ,meeting , restaurant , army etc .Basic function: your voice could heard loudly by others when you speak via headset microphone and voice amplified via speaker box.Other advantage (different model different function ...