... with USB data link, used as speaker*Built-in 3" high power speaker, high sensitivity microphone*Built MCU Intelligent ... waist band*Max output: 18W*Frequency response: 80Hz-12kHz*Speaker: 3" 4Ω*Working voltage:7.4V*Recharging time:Approx 6hrs ... guiding, Morning exercise, Training, Sports, Speech,Publication,Outdoor entertainment Mini Size Rechargeable Portable Voice Amplifier with LED display V-5