Superior battery life gives you more music options. Grind every curb in Burbank. Bike the Everglades. Chill out in your bedroom. Sony gives you more time with up to 70 hours of battery life. The Backlit LCD Display provides easy viewing of song data so you've got more control of your tunes. And with 512MB of built-in memory you can pack your player with up to 345 songs3. Features MP3 playback4 and Skip-Proof Design. Ultra Compact Portable Design Weighing in at less than one ounce the player fits comfortably in the palm of your hand or can easily be carried in a pocket or purse. 512MB Built-In Memory Stores up to 345 songs3 on the device. Up to 70 Hours Battery Life with one ?AAA? Battery Up to 70 hours of continuous playback on one ?AAA? battery. Plays Back MP3/ATRAC3/ATRAC3plus Audio Formats3 For the music connoisseur use the included software and hardware to store and play back your collection of MP3s. For the digital music novice Sony's ATRAC format provides higher sound quality with smaller sizes than many competing formats. This enables you to store more music and have longer listening times. Backlit LCD Display Provides easy viewing of song data and much more. Supports WMA and WAV Audio Formats The Network Walkman player plays back ATRAC3 ATRAC3plus format and MP3 files4 and supports WMA and WAV. Easy Toggle Navigation Navigate through tracks albums and settings by using the large face of the product and rock it back and forth to make a selection. Transfer Personal Downloaded Music and CD Recordings Between your CDs and your PC create your own music mixes for on-the-go enjoyment. Music Management Software Supplied Import manage and easily transfer your digital music collections with the supplied music management software. Skip-Proof Design with No Moving Parts For uninterrupted playback even while carrying the Network Walkman player during active uses. Connects to USB Port for High-Speed Data Transfer After mixes have been created in the jukebox they are easily transferred at high speed to the device. Multi Language Display Displays encoded text that can include the artist name disc name and/or track name. Power: Power Requirements: ?AAA? Alkaline Battery (not included) Battery Life (Approximately): Up to 70 Hours of continuous playback with one ?AAA? Battery (not included)