wireless portable bluetooth speaker 1.single-channel mini speaker 2.supports ipads,iphone , 3.built-in lithium battery wireless portable bluetooth speaker ,mini for mobile/mp3/mp4,aluminum Specification* Power: 3W * Signal To Noise Ratio: >80dB* Frequency Response: 20Hz-20kHz* Battery Capacity: 400mAh* Battery Charging Voltage: 5V* Charger Time: 3 hours max* Last Time: 2-4hours (via bluetooth to ...