3M Safety Ear Plug, Skull Screws Corded #P1301 3M? E-A-R? Skull Screws? push-to fit corded foam earplugs sport the tough look of threaded metal, but feel of soft foam, while offering push-to-fit convenience and noise attenuation with attitude. Effective hearing protection and compliance with a clean, easy twist._ Tough look of threaded metal, but feel of soft foam| Push-to-fit style means no earplug roll down required| Foam tips stay clean, even when your hands are dirty.| Noise Reduction Rating (NRR]* of 30 dB CSA Class AL| New, softer foam| Improved NRR of 32 dB