The Disney Cars Mix Stick is by far the easiest way to play music. Designed especially for kids and teens, its easily portable and has all the elements that kids love and expect these days! 512MB internal memory. Holds up to 240/16 hours of WMA music or 120 songs/8 hours of MP3 music. MP3/WMA. Also stores data - great for homework! MP3/WMA, Built in rechargeable battery (re-charges via USB port). Size: 4.125" L x .1.5" Weight: 1.4oz. Disney Mix Stick , Includes: Windows Media Software CD, Stereo Earbuds, Lanyard w/ Safety Release. Computer Requirements: USB Port Required, Mac and PC compatible, 4 x CD-ROM required. (The Disney Jam Stand is sold separately).