E-A-R Classic plugs are among the most popular earplugs in the world. The yellow color provides high visibility and is an assurance of proven protection. The moisture-resistant non-flammable dermatologically safe foam is non-irritating and its slow recovery provides comfort with low pressure. Fits a wide range of ear canals. Classic Plus provides NRR 33 - the highest NRR available. Tested to ANSI S3.19-1974.