Program: Ali (cycle with players switching function ) Size: 30*44*13mm Battery: (120MA/30MA) play for 4hours USB: 3.5mm hole diameter for earphone PC interface: USB2.0 Color: Black, Sliver, Green, Orange, Red, Blue Capacity: 1GB ~ 4GB available no screen Can be used as USB flash driver with plug-and-play function Support MP3, WMA format compatible with all format music No screen display, aluminum alloy housing, Sport clip design.