Still one of the most widely used foam earplugs today, the 3M™ E-A-R™ Classic™ earplug is an economical, reliable choice in hearing protection and conservation. Slow recovery, low-pressure foam conforms to the shape of the earcanal to help create a comfortable, snug noise barrier. Poly bag keeps disposable earplugs available. Flame-resistant and moisture-resistant Noise Reduction Rating (NRR)*: 29 dB. CSA Class AL.