3M Ear Plugs ( 29 DB ) W/ Tapered Edges, Uncorded ( 200 Per Box )Highlights Noise Reduction Rating (NRR) of 29 dB, CSA Class AL Test compatible with 3M E A Rfit Validation System 3M Foam Earplugs 1100 feature soft, hypoallergenic foam and a tapered design to fit comfortably in the ear canal. The slow recovery polyurethane foam conforms to the shape of the ear canal to help create a comfortable noise barrier. These earplugs are test compatible with the 3M E A Rfit Validation System.