Built-in 18650 battery capacity: 2*1200MA; Supply voltage: 5 volts; Output power: 1*15 watts; Speaker: 57mm, 4 ohms, external magnetic; Frequency response: 100-18Khz; Bluetooth solution: Zhongke 5.4 supports U disk, TF card, Bluetooth call, selfie, interconnection, FM radio, dynamic color screen; Playback time: 2~5 hours (depending on the music and volume, the playback time is also different); Super bass