Peltor Extreme Performance Earmuffs- H10 Series is a high performance hearing protector and has been developed for use in extremely noisy environments. The protection is based on a technology with a double casing minimizing resonance in the casing giving optimum high-frequency attenuation. An acoustic connection between the inner and outer casings provides maximum low-frequency attenuation. The sealing rings are broad and filled with soft plastic foam for the best fit and low contact pressure.