For extreme levels up to 105 dBA. Developed for the ultimate protection in the most demanding noise environments. The OPTIME 105 features added mass and volume, plus a unique double-shell ear cup design. Two cups connected via a foam inner layer to reduce structural resonance that provides maximum noise reduction. The headband fits any head size and designed for over the head use. NRR 29dB. Tested to ANSI S3.19-1974 standard. Sold by the each.