Sony Linear PCM Digital Voice Recorder ICD-SX1000 Built-In 3-Element Stereo Microphone, 5-Second Pre-Record Buffer, Automatic/Manual Record Levels Dual AD Convertors, S-MASTER Digital Amplification Records as PCM or MP3 Files 16GB Internal Flash Memory (up to 636 Hours of Recording Time), microSD Expansion Slot for Added Memory Retractable USB Terminal