Bradychan&reg; 2015 Popular Mini Ultra-small S530 4.0 Stereo Bluetooth Headset in-Ear Headphone Earphone Invisable Earbud for iPhone Android Smartphone (black) Built-in DSP audio processing system, can be a very good eliminate Noise and echo, to ensure clear communication, and music. Bluetooth version:V4.0 + EDR. Can talk, listening to music Small and light, stealth design. Battery type:50mA rechargeable lithium battery 2 in a row, to the telegraph, voice prompt operation