Ear Muffs - Black In addition to being used as noise-reducing ear muffs, the core bar can be extended and adjusted to fit head circumferences up to 56cm, allowing even adult women to use them comfortably. They can be used in various ways, such as for those with hyperacusis, for on-site work, for those who want to escape from noise, or for those who want to concentrate quietly. These ear muffs can be used with confidence as noise reduction ear muffs by a wide range of people, from teens and up. *A head circumference of 56cm is the average head circumference for women. Those with a larger head circumference are not applicable, so please measure the user's head circumference before purchasing. An average NRR (Noise Reduction Rating) of -27dB effectively reduces noise, does not disturb children's sleep, and protects hearing. It efficiently reduces the sound level of high-frequency and other noise bands. The noise-reducing ear muffs use high-density sponge, which has sound absorption and noise reduction properties, and can effectively reduce noise decibels. The ear pads are made of high-quality ABS material, which is resistant to heat and low temperatures, and is resistant to damage and deformation, demonstrating its noise-canceling ability to the fullest. Low-resilience material is also used in the headband to protect the head and provide comfort. These noise-canceling ear muffs can be used by a wide range of people, including infants, children, babies, teens, and those with a head circumference of up to 56cm. Noise canceling creates a quiet environment and improves children's learning and reading efficiency. Shipping: Regular Mail #EarMuffs #SoundproofEarMuffs #EarWarmers #NoiseReduction #Hyperacusis