3M™ E-A-R™ Classic™ Corded Earplugs, Poly Bag 311-1101 Classic earplugs were the industry’s first foam earplugs, virtually revolutionising hearing protection. Today, the revolution continues. It meets more wearer and environmental needs with its proprietary foams, preferred cylindrical shape, and proven in-ear comfort. Optimal in-ear pressure Hydrophobic (repels water) SLC80 21dB (Class 3) 3M proprietary slow recovery foam ensures a good custom fit inside most ear canals Reduces noise levels up to 28 dB