Feature: 1. 300mAh Battery: The mini keychain recorder features a built in 300mAh rechargeable lithium battery that provides up to 20 hours of continuous recording time and can store up to 100 hours of recorded sound files. With voice activation function, it can record for 15 to 20 days. 2. Easy Operation: With a simple one button operation, the recorder is user friendly and supports functions like fast forward, rewind, and time setting. 3. Compact and Portable: The mini keychain recorder is small in size and lightweight, making it easy to carry around. It is perfect for use in classrooms, meetings, interviews, and more. 4. Noise Reduction: With a recording bitrate of up to 192KBPS, the recorder effectively reduces noise, ensuring clear sound. 5. Voice Activated: The recorder includes a voice control feature that automatically starts recording when sound is detected within a 5m / 16.4ft radius. Specification: Item Type: MP3 Player Recorder Material: Aluminum Alloy, Electron Model: S30 Battery Type: Built in 300mAh Lithium Battery (included). Package List: 1 x MP3 (Shipped with Built in Battery) 1 x Wired Earphones 1 x Charging Cable 1 x User Manual