Support 8GB TF card. (TF card NEED you choose when buying) Support MP3 WMA music format. Be able to use directly as a USB portable disk. Just save your files in it! Built-in rechargeable li-on battery. Automatic turn off while not under use for setting time. Enjoy your sports and music at the same

Support 8GB TF card. (TF card NEED you choose when buying) Support MP3 WMA music format. Be able to use directly as a USB portable disk. Just save your files in it! Built-in rechargeable li-on battery. Automatic turn off while not under use for setting time. Enjoy your sports and music at the same time! Operating system: Windows 98/2000/XP/win 7. Output Frequency: 20Hz-20kHz.