ZD70 Smart HD Noise Reduction Voice Control Recording Pen 1. Display: 1.44 color screen 2. Speaker: 23 speakers 3. Headphone interface: 3.5pie stereo jack 4. Distortion rate: about 70dB 5. Signal-to-noise ratio: 0.05% 6. Recording format: WAV format 7. Recording power: 8-20mA 8. Recording acquisition rate: 16-48KHZ 9. Recording bit rate: MP3, WAV 10. USB interface: Type-CDC5V-1A 11. TF card capacity: 4GB-128GB (not included in this product) 12. Battery capacity: 500mAh 13. Recording save: One file is saved every 1 hour by default 14. Continuous working time: about 50 hours of recording, about 50 hours of headphone playback 15. Audio playback time: about 10 hours of continuous external playback (determined by the volume) 16. Support system: Windows XP&Vista2KME98 (need to install driver)Mac OSWindows 7 Windows10 17. Omnidirectional, stereo directional recording 18. 1536Kbps, high-definition lossless sound quality