*Polarized lens & TR 90 frame *Compatible format: MP3, WMA, ADPCM *Available flash memory size: 64MB, 128MB, 256MB, 512MB, 1GB *Standard USB port *Integrated USB drive *Play function: play in order, pause, resume playing etc. *Delete function: delete current or all songs or recordings *Integrated Microphone supporting ADPCM recording. *Continuous playing time: 8 hours *Recharging time: 2 hours *230mAh/3.7V macromolecule polymer li-ion recharging battery *Automatically detected battery voltage and capacity *Battery Consumption Saving function: a- Automatic power off if no button pushed in 2 minutes under pause status b- Automatic power off in 2 minutes when all tracks played *Voice output power: 5mW + 5mW *Voice output frequency: 20Hz ~20KHz