Constructed by solid ABS shell and thickened sound-absorbing foam, the kids ear defenders achieve SNR 26 dB noise-isolation, ANSI S3.19 (US) and CE EN352-1(EU) both certified The adjustable headband features ergonomics telescopic arms on each side, which can be adjusted to cover various head sizes for different ages of kids. No worries about kids’ fast growing Kindly Note: For more efficient sound isolation, the earmuffs are a little tight before using. If you feel tight for your kids, we recommend putting it on a box or other objects for 1-2 days to stretch the headband and get it looser Crafted with skin-friendly materials, the well-padded headband offers maximum comfort and snug fit with less pressure. The 360 degree rotatable cups and ultra-soft ear cushions provide long-lasting comfort. In addition, the holeless pivot frees your worry of hair getting stuck Super lightweight design is for easy carrying, enabling you to bring it to any noisy scenes, such as fireworks, airplane travel, sports events, Disneyland, concert and cinema