Card MP3 Player, Customized mp3 memeber card 1.credit card shape, slim 2.MP3, WMA 3.1G-16Gcapacitity MP3 Card Player, Customized memeber card/ credit card/ ... Capacity: Varies from 1GB to 8GB(optional)5. Support MP3/WMA audio formats6. USB 2.0 interface, high-rate transmission7. Transmission speed ... storage function,11. Size: (L*W*H) 8.5cm * 5.4cm * 0.4cm12. Operation System Supports: Win XP, Win 2000 ...