Features: Easy to wear, low noise, low distortion, for people with severe hearing loss. It is light weight, not easily to be seen. Comfortable for either right or left ear, good performance. Ultra mini size and light weight, not easily to be seen. Adjust volume to the minimum before wearing. Choose an earplug of slightly bigger size to avoid whistler. Increase volume gradually to avoid sudden increase in sound. Specifications: Item Type: Ear Care Brand:No Material: ABS Model Number: no Product Size: Approx. 92*70*27mm Color: Beige Max Saturated Sound Pressure: 125dB+4dB Sound gain: 50dB Harmonic Wave Distortion: 50% Frequency response Range: 300Hz~4000Hz Input Noise: 30 dB Power Voltage :1.5 V Current: 4mA Battery Type: AG13 button cell battery ( not included) Packing content: 1 x Ear Sound Amplifier (batteries are not included) 3 x Earplugs Of Different Size