Best promotion gift credit card shape digital mp3 1.very thin: 5mm 2.Lithium rechargeable battery DescriptionSpecificationsForm of musicMp3 wmaCapacity & Performance128MB, 256MB, 1GB, 2GB, 4GB,8GBUSB InterfacesUSB 2.0, USB1.1 CompatibleData RetentionUp to 10 yearsOS SupportsWin XP, Win 2000, Win ME, Linux 2.4 and above, MAC OS 9.0 and higher, Windows 98/98SE(WITH DRIVER)ConnectorUSB A TypeLED ...