Portable Mini CIC Hearing Aid Invisible Rechargeable Sound Amplifier Collector 1. Adopt high-frequency moving-iron speakers, which can provide clear and delicate sound performance, and can restore the real human voice in the middle and high frequency bands 2. Adopting intelligent chip, which can process the sound source finely, and built-in frequency compensation function, which can restore the real human voice 3. Enjoy a comfortable listening experience, balanced armature speakers, adaptive noise reduction mode, stepless tuning, easier to control the volume 4. Long battery life, magnetic base, Type-C interface, after a full charge, can be used continuously for 30 hours, do not have to worry about the power problem 5. Invisible wearing, small and lightweight, adapt to various ear canal shapes, long time wearing without pressure, so you can enjoy the fun of listening immersively Specification parameters: 1. Shell material: ABS 2. Rated voltage: 3.7V 3. Charging interface: Type-C 4. Charging time: about 2h 5. Duration: about 30h 6. Host battery capacity: 35mAh 7. Maximum saturation OSPL90 (db): below 114.07db±3db 8. High frequency mean OSPL90 (db): 112.82db±3db 9. Full tone gain: 29.37±5db 10. Frequency response range: not narrow to 350Hz-5000Hz 11. Total harmonic distortion: less than 3% 12. Equivalent input noise level: less than 22.86db ± 3db 13. Rated power current consumption: less than 1.2mA 14. Weight: the whole machine about 38g, a single about 2g