Featuresr you must connect your phone with bluetoothr the product with microphone convenient to user the string of headset is retractable fit different peopler with external audio line function you can use it as ordinary earphone in computer and phonewithout bluetooth functionr with volume key and pause key convenient to user made of high quality material durabler support tf card you can get different music16g without tf cardr it is 90rotation convenient to storager it has hi