Howard Leight™ Lightning and thunder cap mounted earmuff with North® hard hats, face shields and 23 dB NRR. Face shield slot design allows for attachment of North face shield visors for complete integrated protection on the job. Hard hat clip easily and securely attaches earmuffs to several models of North hard hats. Fork design simply press down on the fork to snap earmuffs into place. For construction, forestry, mining, steel and metals applications.