Soft, roll-down foam earplugs expand to fit the earcanal and provide a low-pressure, comfortable seal. Poly bag keeps each pair of earplugs clean before use. CSA Class AL. Test compatible with 3M™ E-A-Rfit™ Validation System. However, research suggests that many users will receive less noise reduction than indicated by the NRR due to variation in earplug fit, earplug fitting skill, and motivation of the user. It is recommended that the NRR be reduced by 50% to better estimate typical workplace protection. Corded/Cordless: Cordless; Shape: Tapered; Material(s): Polyurethane; Noise Reduction Rate (NRR): 32 dB.