Ears need protection from excessive and prolonged noise. Noise reduction rate (NRR) of 30dB. Attenuation tested in accordance with ANSI S3.19-1974. Bright green for visual safety check. Low pressure foam earplugs offer long-term user comfort not found in other pre-shaped foam earplugs. The non-irritating, non-allergenic self-adjusting foam recovers to fit virtually any ear canal.