The E-A-R Classic SuperFit 33 orange "fitting ring" provides a guideline for proper insertion and quick visual compliance check. Another innovation from 3M, E-A-R Classic SuperFit 33 has a built-in visual check - the orange fitting ring. If the ring is visible after insertion, refitting is recommended for best hearing protection. - reusable pillow pack helps keeps earplugs clean when they are not being worn. - conforms to the shape of the earcanal to help create a comfortable, snug noise barrier - slow recovery earplug foam is flame resistant and moisture resistant - noise reduction rating (NRR): 33 dB CSA class AL. - test compatible with 3M E-A-Rfit validation System.

The NRR may overestimate the hearing protection provided during typical use. 3M recommends reducing the NRR by 50% for estimating the amount of noise reduction provided. 3M is leading the advancement of hearing Conservation.