Hearing aid sound amplifier Super mini size and light weight, not easily to be seen Adjust sound to the minimum before wearing Increase sound gradually to avoid sudden increase in sound Convenient for watching movie, enjoying the drama, attending meeting, or having class, it could help you hear the sound clearly and loudly Specification: Mini ITE Hearing aid: Max Sound Output: =120 dB Max Sound Gain: =30 dB Harmonic Wave Distortion: f<1000Hz=10%, f;;;1000Hz=4% Frequency Range: 250~3800 Hz Input Noise: =50 dB Battery: 1 x AG3 Button battery Working Voltage: dc1. 5V Working Current: =4mA Color: As the picture shows Item Size: 2. 2 x 1. 9 x 1. 5cm Package Size: 9. 6 x 8. 2 x 3. 4cm.