Bluetooth version: 4.2 Function:Bluetooth/AUX/TF Card/Handfree/USB drive Internal magnetic 16 core*2 output power: 3W*2 Input:5.0V Loud speaker:40mm *2 4Ω / 3W Signal and noise ratio(SNR):70db Frequency Response:18HZ-18KHZ Output distortion rate≤0.5% Battery: 1200mAH Material: ABS Color: black/ red/blue/white Working time:3 hours