Sony NW-E103PS Network Walkman 256 MB Digital Music Player (Black) Small, round multiformat digital audio player weighs under 1 ounce 256 MB built-in flash memory stores up to 170 songs Plays MP3, ATRAC, and ATRAC3 formats; supports WMA, WAV Compatible with content purchased from Sony's Connect online music store Single AAA battery provides up to 70 hours of battery life; connects to Windows PCs via USB 2.0