Unique design fits for holding. Support MP1/2/3, WMA, WMV, ASF files. FM radio function. Built-in phone book. Private space available. Voice recording and repeat function. 7 backlight color provided. Equalizer in normal, rock, pop, classic, soft, jazz and bass available. Play modes in normal, single repeat, play catalog, repeat all, repeat catalog and shuffle available. Timing turn-off. Complete dynamic menu. High speed USB interface. Firmware upgrade support. Built-in rechargeable lithium battery for about 5 hours of playing.