Docooler AEC BQ-621 Neck-strap Style Wireless Bluetooth headphone Sport Bluetooth 4.1 + EDR Hands-free earphone with Microphone Enjoy music wirelessly, easy to switch between calls and music, you will not miss any incoming call whilst listening to music. Flexible neck-strap with memory function (Easy to carry and custody). Built-in dual microphone for noise reduction. Support hands-free call and smart voice prompt navigation. Built-in high-sensitivity microphone, answer & end a call at click of a button. With 3D soundtrack, and support vibration function (boot up, shutdown, incoming call, etc)