Constructed by solid ABS shell and thickened sound-absorbing foam, the kids ear defenders achieve SNR 27 dB noise-isolation, ANSI S3.19 (US) and CE EN352-1(EU) both certified, which can reduce sensory overload, perfect for kids with autism or sensory issues The adjustable headband features ergonomics telescopic arms that can stretch up to 32 mm/ 1.3 inch on each side, which makes it possible 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° rotatable cups and ultra-soft ear cushions provide long-lasting comfort. In addition, the holeless pivot frees your worry of hair getting stuck Compact folding design is for easy storage and convenient portability, enabling you to bring them to any noisy scenes, such as monster jam truck show, fireworks, airplane travel, sports events, Disneyland and concerts