Voice volume indicator directly shows the sound input volume on display. ClearVoice adjusts quiet passages dynamically, thus improving the intelligibility of quieter voices. Voice-activation function for hands-free recording. MP3 recording is the common audio for consumer audio storage. Rapidly transfer recordings and data via USB 2.0. Instant 1-touch recording-press and hold the record button to instantly start recording. Supports up to 99 recordings in each of 4 available folders to organize files. Plug-and-play in Windows, Mac OS and Linux. Lightweight and ergonomic design. Built-in round dynamic front speaker for crystal-clear voice playback. Hold function deactivates all buttons to prevent accidental key presses. Recording time: 544 hours (SLP), 140 hours (LP), 92 hours (SP), 70 hours (HQ). Requires 1 AAA battery (included). Includes USB cable