Features: 1) Diameter: 34mm 2) Supports MP3 and WMA audio formats 3) Built-in rechargeable lithium battery 4) Built-in multiple EQ modes 5) Mobile storage function 6) USB 2.0 (FS) high-rate transmission 7) Accessories: a) Earphone b) USB cable c) Charger d) CD drive Inner packing: Magnetic gift boxes