Features 1.VOLUME ADJUSTMENT: Rechargeable sound amplifier is a great choice. You can adjust the volume as you like while watching TV and movies, attending meetings or classes. 2.NOISE CANCELLATION: Input noise is less than 30dB with less than 5% harmonic distortion, and the N H mode switching and microphone and hearing aid separation design help reduce noise. 3.H MODE AND N MODE: Hearing aid headphones provide clear sound outdoors in H mode and a more comfortable experience indoors in N mode to meet your different usage needs. 4.EQUIPPED WITH EARMUFFS: Digital hearing aids come with 4 different shaped earmuffs and 4 replacement earmuffs for a snug fit for different ear types without worrying about dropping or losing them. 5.LOW CURRENT AND POWER SAVING: Hearing aids have a built in lithium battery with a capacity of 120mAh, which can work continuously for about 20 hours after a full charge, featuring low current and power saving. specificationItem Type: Hearing Aid Headphones Material: ABS Maximum Sound Output: 1305dB Sound Gain: 45dB+5dB Total Harmonic Distortion: 5% Frequency Range: 450Hz-3000Hz Input Noise: 30dB Battery Type: Built In 120mAh Lithium Ion Battery Voltage: 100-240V PackageList 1 x Host 1 x Earphone 8 x Earbuds 1 x Data Cable 1 x Power Adapter 1 x Instruction Manual