The Hunter Passive is for hunting environments where a low number of shots are fired. It utilizes small orifice non-linear acoustic filters, and a low NRR of 4 allows for awareness of game and tracking dog sounds, as well as easier communication with hunting/shooting partners. For other impulsive noise environments with impulses below 160 dB peak SPL for adults, employing filters utilizing small orifice non-linear acoustics.
IPIL Ratings (Impulsive Peak Insertion Loss according to ANSI S12.42-2010)
Attenuation @ 132 dB = 15.1 dB
Attenuation @ 150 dB = 22.8 dB
Attenuation @ 168 dB = 26.7 dB
Impulses below 160 dB peak SPL