Skullerz 8881 Non-Conductive Hard Hat Mounted Earmuffs easily mounts onto Skullerz Cap-Style, Climber-Style and Full Brim Hard Hats, Safety Helmets and Face Shields for increased hearing protection. They are tested and certified to meet ANSI/ISEA S3.19-1974 standard. As noise reducers, these earmuffs are tested and certified to either 25 dB or 27 dB NRR depending on head protection type. They offer shock-safe protection. Nonconductive arms have no metal parts and offer 1000V electrical protection. Low-profile, lightweight design allows easier movement in tight spaces and reduces snag hazards on busy jobsites. Pressure-reducing foam cushions provide a comfortable fit. Long-lasting ABS construction on earcups offers protection in tough environments.