Feature:1. [With Adjustable Volume] The knob type sound control is convenient for you to adjust the volume according to your needs.2. [Practical Hearing Device] This hearing device is designed for old people or people with hearing problems.3. [With Silicone Earplugs] Silicone earplugs are soft and elastic, effectively relieving your ear discomfort.4. [Easy to Hear the World] The hearing aid device has clear sound quality and big power can be used for compensation for hearing loss.5. [Wear Comfortably] Easy to wear design, conform to your ear shape, stable wearing and can ensure comfort.Specification:Item Type: Hearing AmplifierMaterial: ABSMaximum Sound Output: 129+3dBSound Gain: >= 40dB±5dBTotal Harmonic Distortion: < 10%Frequency Range: 1000-4000MHzInput Noise: <32dBCurrent: <=1.2mABuilt in Lithium Battery Capacity: 25mAh (included).Package List:1 x Storage Box3 x Earplug1 x Brush1 x Hearing Amplifier 1 x Charging Cable1 x Manual