The Intelligent Auto Mode automatically adjusts the microphone sensitivity according to the volume of the sound source. PCM/MP3/WMA stereo recording. Music player. 8 Gb for 2,000 hours of recording time. microSD card slot. USB direct connector, no cable needed. 5 folders, 200 messages per folder. Calendar search function. Auto scene adjustment. Up to 99 index marks. Powered by one AAA battery.