SanDisk Sansa e130 512 MB Digital Audio Player with SD Expansion Slot 512 MB MP3 player holds up to 120 MP3 files and up to 240 WMA files, SDexpansion slot lets you add up to 2 GB of additional memory Plays MP3, WMA (including secure WMA content), Audible audio file formats Hi-Speed USB 2.0 port for fast and easy transfer of files Digital FM tuner with 20 preset stations Up to 17 hours continuous playback using one AAA battery