3M E-A-R Classic Uncorded Earplugs, Hearing Conservation 312-1201 in Poly Bag, 200 pairs 3M E-A-R Classic Earplugs set the standard in hearing protection as the world's first foam earplugs Slow recovery, low pressure foam conforms to the shape of the ear canal for enhanced comfort and wearability Moisture resistance helps maintain a consistent expansion time, even in humid situations Noise Reduction Rating (NRR) 29 dB. CSA Class AL Flame resistant for potential arc flash situations and safer storage