Dr. Meter EM100 Protective Earmuffs for sleeping or studying. These come with an adjustable head band, a safe and comfortable design tailored for smaller ears. 27NRR noise reduction rating, ideal for blocking noise caused in large crowds, noisy homes, airports, construction sites and daily life. Though the earmuffs are designed to suit children's features, the adjustable soft PU leather headband fits all head sizes. The padded ear cushion gives a comfortable snug fit and enhanced noise blocking ability.  Thanks to 360 rotatable cups, its whole body can be folded into very compact size, it is lightweight and portable. ANSI S3.19 tested & certified (American national standards Institute) and CE EN 352.1 tested & certified (European standard).