Audio format supported: MP3 and WMA Lyric Synchronization,display ID3 song title 5-way Navigation Key and Enter Key.easy to operate OLED display with 7 backlight colors 7EQ modes(Natural/Rock/Pop/Classic/Soft/Jazz/DBB) Multi-language support, Graphic user interface,easy to operate. Built-in FM tunner(Optional) Bulit-in high capacity lithium battery.Directly plugged into computer USB port for file/music transfer and recharge ,which can last up to 18 hours in operation. Shutdown memorize function. Digital voice recording function Digital voice recording support. WAV(ADPCM) format Bulit-in high capacity lithium battery. which can last up to 15 hours in operation key lock supporting in case of mis-operating, easy to take. Lovers phone jack (one is phone jack and the other is through bluetooth transmissiion) Lyric and melody synchronization Capacity Extension Slot: Supporting Micro SD,Extension Storage Space Built-in bluetooth function (Class2,Version 1.2).supporting A2DP profile