Noise-proof earmuffs are usually made of absorbent materials or highly elastic materials. After wearing, the earmuffs will isolate the ears to prevent sound from entering the middle ear and inner ear (ear drum), thereby achieving the of noise reduction, so that people can get a quiet rest or working environment. Many high-decibel operating environments will seriously affect the hearing safety of workers, so a reasonable choice should be made according to the actual site environment. Soundproof earmuffs reduce the possibility of damage to the operator's hearing. Soundproof earmuffs are a product that can significantly reduce noise and protect ears. It is widely used in with high noise such as factories and airports. Streamlined design, sound-absorbing ear pads are light, soft and comfortable; fully handle high-frequency and low-frequency noise and reduce average noise; widely used in high-noise areas such as factories and construction sites. Noise reduction: NRR: 21dB Colour:blue Material:ABS+sponge Size: 16 x 12 x 4.6cm Package Contents: 3 x Ear Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Ear Noise cancelling ear