Type III-A: with fixed headband. The best choice for extreme noise exposure. This hearing protector is based on a new technology; double shells minimize resonance in the capsule. In this way, maximum high-frequency attenuation is achieved, but signals and speech can be easily perceived at the same time. The acoustic connection between the interior and the space between the shells ensures optimum attenuation of low frequencies. The wide sealing rings filled with soft foam guarantee a good fit and weak pressure.