EN-T201A Digital Machine Elderly Charging Hearing Aid Sound Amplifier 1. OSPL90: less than or equal to132dB 2. High frequency average OSPL90:120dB 3. Full gear sound gain: 35dB±5dB 4. Equivalent input noise: less than or equal to29dB 5. Working current: 10mA 6. Frequency range (not narrower than) : 300Hz to 4500Hz 7. Battery capacity: 30mah 8. Battery type: Rechargeable polymer lithium-ion battery 3.7V 9. Ergonomic design ear hook, comfortable to wear, ear will not hurt 10. Adopt digital signal processing technology, adapt to a variety of auditory environment, present natural sound quality, let the sound clear transmission 11. One key noise reduction technology, easy to feel the natural sound 12. Three modes can be switched freely 13. USB charging design, rechargeable, blue light when charging, green light when fully charged 14. Cycle charging, built-in lithium polymer battery, durable endurance, long service time 15. One-button switchmode switch. Long press is switch on and off, short press is mode switch 16. Small body, hidden in the back of the ear, easy to wear, easy to take off 17. Intelligent noise reduction processing chip, double noise reduction, analysis and remove all kinds of noise 18. Anti - sweat and anti - fall, durable 19. Size: 3.48x1.7x0.85cm 20. Weight: 4g