... and clear sound.Super small. Type:waistband amplifier/Mini speakerSpecitification:Operating Temperature: -10~+50°CUsed for full ... time 4 ~ 6 hours.Feature:USB,TFcard,FM audio,LED displaylibretto synchronizer,Reverberation effect,with ... This mini speaker is widely used at home, office , school , church , factory , hospital ,meeting , restaurant ,etc . Mini portable mp3 pa speaker music