USB 2.0 Sport MP3 Player General Features: Color: Black Supports up to 4 GB storage</br>Comfortable behind-the-head stereo headphones with built-in controls and LED indicator</br>Built-in Lithium-polymer battery Supports MP3?? WAV and WMA formats USB 2.0 high-speed interface</br>Specifications: Lithium-Ion Battery Audio Formats: MP3/WMA/WAV S/N Ratio: 86dB Output Frequency: 20Hz - 20 kHz</br>Package include : (1)1x Headset MP3 Player (2)1x Mini USB to USB cable</br></br>Product Description</br></br><br />Buttons: Play / Pause?? Previous?? Next?? ON/OFF <br />Press and hold " / Pause" to stop playing music. <br />Press "Previous" or "Next" to go to the previous or next song. <br />Press and hold "Previous" or "Next" to increase or decrease volume. <br />Music play format: MP3 ( please note that other formats cannot play music ) <br />Support playing time: about 3 hours <br />When it cannot be recognized by computer connecting?? please turn off headset?? unplug USB port??restart and connect it with computer.</br><br/>http://www.amazon.com/gp/product/B00K5SV6L4ddin