Smooth, dirt-resistant surface for better hygiene Comfortable for a wide range of ear canal sizes Easy to roll down for quick, easy fitting Hypoallergenic, soft polyurethane foam Great for metal fabrication, automotive and more Soft, uncorded earplugs conform to the unique shape of each ear for excellent hearing protection and comfort. Tapered design fits comfortably in the ear canal and offers a smooth, dirt-resistant surface for hygiene. Earplugs are made of soft, hypoallergenic foam. Noise Reduction Rating (NRR) is 29 decibels. CSA Class AL. Earplugs are test-compatible with 3M E-A-Rfit Validation System.