Bluetooth 1.2 V Range: Class 2,10 meters Combination of Bluetooth and MP3:When calls come in the mp3 player will suspend and shift to bluetooth operation. When it come back to bluetooth operation PC interface supported:USB Digital formats supported: MP3/WAV/WMA Signal-to-noise ratio:87.2dB Playback Modes:Random play External hard drive function: Yes Sound output mode: Stereo Audio Additional features:Auto-power off Earphones type: Binaural Mfr estimated battery life : 6hours continuous Charging Time:3hours continaully Battery tape/capacity: Built-in Lithium lon Polymenr/3.7v,150mAh Maximum imput power rating:5VDC,150mA Voice output power:55mW Voice output frequency:20Hz-20Khz earphone impendance:16 ¦¸*2 Memory Flash:128MB-1G