OOOUSE Mystore365 Black 2gb Headset Sunglass Mp3 Player Sun Glass Extremely comfortable and secure for the most users, Bicyclist, Runners, Joggers, Hiker etc. 2GB Built-in Flash Memory Powered by USB port or wall charger Audio format: MP3, WMA, WMV, ASF, OGG, With stereo earphone! Battery: Build in Li-ion battery.(3.7V 150MAH)