These earmuffs are ideal hearing protection in extremely noisy environments like airports marine engine rooms power stations and print works. The double casing technology helps minimise resonance effect. The large space inside the cup helps reduce moisture and heat build-up and reduces pressure around the ears to improve comfort and wearability. The cushions are very easy to replace which helps to keep them hygienic. It has been tested and approved to the CE Approved EN 352-3:2002 standard.