Sized for smaller ear canals and bell shaped for easier insertion and removal on the job. Soft, slow-recovery foam rolls down easily then expands in the ear canal to provide comfortable hearing protection. Flexible cord keeps earplugs connected. Poly bag keeps each pair of earplugs clean before use. Noise Reduction Rating (NRR)*: 28 dB. CSA Class AL. *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.