Good Noise Reducation：GREEN DEVIL Behind the head noise reduction safety earmuffs offers a SNR 27dB / NRR 22dB (Noise Reduction Rating) for our hearing protection.Providing existing protective gear with a superior level of hearing protection to help complete comprehensive above-the-neck safety systems.Help reduce exposure to hazardous levels of noise，ideal for protection against noise arising from a wide range of applications in the workplace. Practical Behind-the-head Design：It's very handy when wearing other PPE such as a face shield. fit well with most helmets, eyewear, and other safety equipment.High recommend it for someone who don't like the in-the-ear hearing protection or over-the-head hearing protection ear muffs. Super Lightweight and Comfortable ：Generous space inside the low-profile ear cups ensure breathability meanwhile soft imitation leather provides a tight sound-proof seal .Ergonomic headband with soft padding reduces the pressure on your head for superior comfort. Extra Anti-slip Headband Design：Comes with a headband with velcro that keeps the ear cups on your head without worrying about slipping off when using.When you don't want to use the headband, you can also roll up the Velcro headband. Safety & Compliance：Earmuff’s Stainless steel construction resists bending and warping,adapt to various environments without worrying about being damaged.GREENDEVIL Behind the Head noise reduction ear protection ear muffs headphones are approved by ANSI S3.19-1974 and EN352-3 and meets all applicable OSHA regulations.If you have any questions, welcome to reach us，we will make things right, FAST!