When it comes to selecting an earmuff, comfort reigns supreme with workers. That's why the Thunder series earmuff is designed with all-day comfort in mind. Headband earmuffs feature a unique dual-headband for better positioning and breathability, and non-deforming outer headband that minimizes pressure on the head. Plus, its dielectric construction withstands use and abuse, while protecting workers in electrical environments. Three-position headband fits any head size and can be worn over the head, behind the head or under the chin. NRR 30dB. Tested to ANSI S3.19-1974 standard. Sold by the each.